Diagnosis of asthma: diagnostic testing.

Science.gov (United States)

Brigham, Emily P; West, Natalie E

2015-09-01

Asthma is a heterogeneous disease, encompassing both atopic and non-atopic phenotypes. Diagnosis of asthma is based on the combined presence of typical symptoms and objective tests of lung function. Objective diagnostic testing consists of 2 components: (1) demonstration of airway obstruction, and (2) documentation of variability in degree of obstruction. A review of current guidelines and literature was performed regarding diagnostic testing for asthma. Spirometry with bronchodilator reversibility testing remains the mainstay of asthma diagnostic testing for children and adults. Repetition of the test over several time points may be necessary to confirm airway obstruction and variability thereof. Repeated peak flow measurement is relatively simple to implement in a clinical and home setting. Bronchial challenge testing is reserved for patients in whom the aforementioned testing has been unrevealing but clinical suspicion remains, though is associated with low specificity. Demonstration of eosinophilic inflammation, via fractional exhaled nitric oxide measurement, or atopy, may be supportive of atopic asthma, though diagnostic utility is limited particularly in nonatopic asthma. All efforts should be made to confirm the diagnosis of asthma in those who are being presumptively treated but have not had objective measurements of variability in the degree of obstruction. Multiple testing modalities are available for objective confirmation of airway obstruction and variability thereof, consistent with a diagnosis of asthma in the appropriate clinical context. Providers should be aware that both these characteristics may be present in other disease states, and may not be specific to a diagnosis of asthma. © 2015 ARS-AAOA, LLC.

Evaluation of tuberculosis diagnostics in children: 1. Proposed clinical case definitions for classification of intrathoracic tuberculosis disease. Consensus from an expert panel.

Science.gov (United States)

Graham, Stephen M; Ahmed, Tahmeed; Amanullah, Farhana; Browning, Renee; Cardenas, Vicky; Casenghi, Martina; Cuevas, Luis E; Gale, Marianne; Gie, Robert P; Grzemska, Malgosia; Handelsman, Ed; Hatherill, Mark; Hesseling, Anneke C; Jean-Philippe, Patrick; Kampmann, Beate; Kabra, Sushil Kumar; Lienhardt, Christian; Lighter-Fisher, Jennifer; Madhi, Shabir; Makhene, Mamodikoe; Marais, Ben J; McNeeley, David F; Menzies, Heather; Mitchell, Charles; Modi, Surbhi; Mofenson, Lynne; Musoke, Philippa; Nachman, Sharon; Powell, Clydette; Rigaud, Mona; Rouzier, Vanessa; Starke, Jeffrey R; Swaminathan, Soumya; Wingfield, Claire

2012-05-15

There is a critical need for improved diagnosis of tuberculosis in children, particularly in young children with intrathoracic disease as this represents the most common type of tuberculosis in children and the greatest diagnostic challenge. There is also a need for standardized clinical case definitions for the evaluation of diagnostics in prospective clinical research studies that include children in whom tuberculosis is suspected but not confirmed by culture of Mycobacterium tuberculosis. A panel representing a wide range of expertise and child tuberculosis research experience aimed to develop standardized clinical research case definitions for intrathoracic tuberculosis in children to enable harmonized evaluation of new tuberculosis diagnostic technologies in pediatric populations. Draft definitions and statements were proposed and circulated widely for feedback. An expert panel then considered each of the proposed definitions and statements relating to clinical definitions. Formal group consensus rules were established and consensus was reached for each statement. The definitions presented in this article are intended for use in clinical research to evaluate diagnostic assays and not for individual patient diagnosis or treatment decisions. A complementary article addresses methodological issues to consider for research of diagnostics in children with suspected tuberculosis.

Evaluation of Tuberculosis Diagnostics in Children: 1. Proposed Clinical Case Definitions for Classification of Intrathoracic Tuberculosis Disease. Consensus From an Expert Panel

Science.gov (United States)

Graham, Stephen M.; Ahmed, Tahmeed; Amanullah, Farhana; Browning, Renee; Cardenas, Vicky; Casenghi, Martina; Cuevas, Luis E.; Gale, Marianne; Gie, Robert P.; Grzemska, Malgosia; Handelsman, Ed; Hatherill, Mark; Hesseling, Anneke C.; Jean-Philippe, Patrick; Kampmann, Beate; Kabra, Sushil Kumar; Lienhardt, Christian; Lighter-Fisher, Jennifer; Madhi, Shabir; Makhene, Mamodikoe; Marais, Ben J.; McNeeley, David F.; Menzies, Heather; Mitchell, Charles; Modi, Surbhi; Mofenson, Lynne; Musoke, Philippa; Nachman, Sharon; Powell, Clydette; Rigaud, Mona; Rouzier, Vanessa; Starke, Jeffrey R.; Swaminathan, Soumya; Wingfield, Claire

2012-01-01

There is a critical need for improved diagnosis of tuberculosis in children, particularly in young children with intrathoracic disease as this represents the most common type of tuberculosis in children and the greatest diagnostic challenge. There is also a need for standardized clinical case definitions for the evaluation of diagnostics in prospective clinical research studies that include children in whom tuberculosis is suspected but not confirmed by culture of Mycobacterium tuberculosis. A panel representing a wide range of expertise and child tuberculosis research experience aimed to develop standardized clinical research case definitions for intrathoracic tuberculosis in children to enable harmonized evaluation of new tuberculosis diagnostic technologies in pediatric populations. Draft definitions and statements were proposed and circulated widely for feedback. An expert panel then considered each of the proposed definitions and statements relating to clinical definitions. Formal group consensus rules were established and consensus was reached for each statement. The definitions presented in this article are intended for use in clinical research to evaluate diagnostic assays and not for individual patient diagnosis or treatment decisions. A complementary article addresses methodological issues to consider for research of diagnostics in children with suspected tuberculosis. PMID:22448023

Methodology of diagnostic tests in hepatology

DEFF Research Database (Denmark)

Christensen, Erik

2009-01-01

The performance of diagnostic tests can be assessed by a number of methods. These include sensitivity, specificity,positive and negative predictive values, likelihood ratios and receiver operating characteristic (ROC) curves. This paper describes the methods and explains which information...... they provide. Sensitivity and specificity provides measures of the diagnostic accuracy of a test in diagnosing the condition. The positive and negative predictive values estimate the probability of the condition from the test-outcome and the condition's prevalence. The likelihood ratios bring together......' and plotting sensitivity as a function of 1-specificity. The ROC-curve can be used to define optimal cut-off values for a test, to assess the diagnostic accuracy of the test, and to compare the usefulness of different tests in the same patients. Under certain conditions it may be possible to utilize a test...

Testing Pneumonia Vaccines in the Elderly: Determining a Case Definition for Pneumococcal Pneumonia in the Absence of a Gold Standard.

Science.gov (United States)

Jokinen, Jukka; Snellman, Marja; Palmu, Arto A; Saukkoriipi, Annika; Verlant, Vincent; Pascal, Thierry; Devaster, Jeanne-Marie; Hausdorff, William P; Kilpi, Terhi M

2017-12-15

Clinical assessments of vaccines to prevent pneumococcal (Pnc) community-acquired pneumonia (CAP) require sensitive and specific case definitions, but there is no gold standard diagnostic test. To develop a new case definition suitable for vaccine efficacy studies, we applied latent class analysis (LCA) to the results from seven diagnostic tests for Pnc etiology on clinical specimens from 323 elderly radiologically-confirmed pneumonia cases enrolled in The Finnish Community-Acquired Pneumonia Epidemiology study during 2005-2007. Compared to the conventional use of LCA, which is mainly to determine sensitivities and specificities of different tests, we instead used LCA as an appropriate instrument to predict the probability of Pnc etiology for each CAP case based on their test profiles, and utilized the predictions to minimize the sample size that would be needed for a vaccine efficacy trial. When compared to the conventional laboratory criteria of encapsulated Pnc in blood culture or in high-quality sputum culture or urine antigen positivity, our optimized case definition for PncCAP resulted in a trial sample size which was almost 20,000 subjects smaller. We believe that our novel application of LCA detailed here to determine a case definition for PncCAP could also be similarly applied to other diseases without a gold standard. © The Author(s) 2017. Published by Oxford University Press on behalf of the Johns Hopkins Bloomberg School of Public Health.

Cost-effectiveness of using a molecular diagnostic test to improve preoperative diagnosis of thyroid cancer.

Science.gov (United States)

Najafzadeh, Mehdi; Marra, Carlo A; Lynd, Larry D; Wiseman, Sam M

2012-12-01

Fine-needle aspiration biopsy (FNAB) is a safe and inexpensive diagnostic procedure for evaluating thyroid nodules.Up to 25% of the results from an FNAB, however, may not be diagnostic or may be indeterminate, leading to a subsequent diagnostic thyroid surgery. A new molecularly based diagnostic test could potentially reduce indeterminate cytological results and, with high accuracy, provide a definitive diagnosis for cancer in thyroid nodules. The aim of the study was to estimate the cost-effectiveness of utilizing a molecular diagnostic (DX) test as an adjunct to FNAB, compared with NoDX, to improve the preoperative diagnosis of thyroid nodules. We constructed a patient-level simulation model to estimate the clinical and economic outcomes of using a DX test compared with current practice (NoDX) for the diagnosis of thyroid nodules. By using a cost-effectiveness framework, we measured incremental clinical benefits in terms of quality-adjusted life-years and incremental costs over a 10-year time horizon. Assuming 95% sensitivity and specificity of the Dx test when used as an adjunct to FNAB, the utilization of the DX test resulted in a gain of 0.046 quality-adjusted life-years (95% confidence interval 0.019-0.078) and a saving of $1087 (95% confidence interval $691-$1533) in direct costs per patient. If the cost of the Dx test is less than $1087 per test, we expect to save quality-adjusted life-years and reduce costs when it is utilized. Sensitivity of the DX test, compared with specificity, had a larger influence on the overall outcomes. Copyright © 2012 International Society for Pharmacoeconomics and Outcomes Research (ISPOR). Published by Elsevier Inc. All rights reserved.

Diagnostic accuracy of high-definition CT coronary angiography in high-risk patients

International Nuclear Information System (INIS)

Iyengar, S.S.; Morgan-Hughes, G.; Ukoumunne, O.; Clayton, B.; Davies, E.J.; Nikolaou, V.; Hyde, C.J.; Shore, A.C.; Roobottom, C.A.

2016-01-01

Aim: To assess the diagnostic accuracy of computed tomography coronary angiography (CTCA) using a combination of high-definition CT (HD-CTCA) and high level of reader experience, with invasive coronary angiography (ICA) as the reference standard, in high-risk patients for the investigation of coronary artery disease (CAD). Materials and methods: Three hundred high-risk patients underwent HD-CTCA and ICA. Independent experts evaluated the images for the presence of significant CAD, defined primarily as the presence of moderate (≥50%) stenosis and secondarily as the presence of severe (≥70%) stenosis in at least one coronary segment, in a blinded fashion. HD-CTCA was compared to ICA as the reference standard. Results: No patients were excluded. Two hundred and six patients (69%) had moderate and 178 (59%) had severe stenosis in at least one vessel at ICA. The sensitivity, specificity, positive predictive value, and negative predictive value were 97.1%, 97.9%, 99% and 93.9% for moderate stenosis, and 98.9%, 93.4%, 95.7% and 98.3%, for severe stenosis, on a per-patient basis. Conclusion: The combination of HD-CTCA and experienced readers applied to a high-risk population, results in high diagnostic accuracy comparable to ICA. Modern generation CT systems in experienced hands might be considered for an expanded role. - Highlights: • Diagnostic accuracy of High-Definition CT Angiography (HD-CTCA) has been assessed. • Invasive Coronary angiography (ICA) is the reference standard. • Diagnostic accuracy of HD-CTCA is comparable to ICA. • Diagnostic accuracy is not affected by coronary calcium or stents. • HD-CTCA provides a non-invasive alternative in high-risk patients.

Standardized Definitions for Code Verification Test Problems

Energy Technology Data Exchange (ETDEWEB)

Doebling, Scott William [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

2017-09-14

This document contains standardized definitions for several commonly used code verification test problems. These definitions are intended to contain sufficient information to set up the test problem in a computational physics code. These definitions are intended to be used in conjunction with exact solutions to these problems generated using Exact- Pack, www.github.com/lanl/exactpack.

The interpretation of diagnostic tests

International Nuclear Information System (INIS)

Lamk, M.; Lamki, M.D.

1987-01-01

The progress of nuclear and other diagnostic imaging is near rampant. With almost every issue of the major journals in this field, a new diagnostic test, or at least a new utility of an old test is described. Before we accept these innovations, we have to have a clear understanding of the clinical performance of the test. The major criteria are the sensitivity and the specificity of the test. From these derived other statistical parameters such as accuracy or efficiency of that test; also, the receiver operating characteristic (ROC) curves may then be evaluated and used in comparison of different tests. When we know the prevalence of the disease tested in the population we are investigating, we can then derive the predictive value of a positive or a negative result. This introduction tries to explain these parameters to help the reader understand the literature dealing with the subject of efficacy of imaging procedures. It is not intended as a critical review of the literature on the subject or a comprehensive overview of the subject matter. The benefit derived from explaination of statistical concepts to physicians is documented in a recent publication. Explaination of these basic statistical parameters will be followed by a demonstration of the utility of multiple testing with these parameters. The reader is thereby introduced to relevant statistical concepts that must be grasped for full comprehension of published results of a new diagnostic imaging modality, or before clinical decision making

Diagnostic tests based on human basophils

DEFF Research Database (Denmark)

Kleine-Tebbe, Jörg; Erdmann, Stephan; Knol, Edward F

2006-01-01

-maximal responses, termed 'intrinsic sensitivity'. These variables give rise to shifts in the dose-response curves which, in a diagnostic setting where only a single antigen concentration is employed, may produce false-negative data. Thus, in order to meaningfully utilize the current basophil activation tests....... Diagnostic studies using CD63 or CD203c in hymenoptera, food and drug allergy are critically discussed. Basophil-based tests are indicated for allergy testing in selected cases but should only be performed by experienced laboratories....

Parameters and definitions in applied technique quality test for nuclear magnetic resonance imaging system (NMRI)

International Nuclear Information System (INIS)

Lin Zhikai; Zhao Lancai

1999-08-01

During the past two decades, medical diagnostic imaging technique has achieved dramatic development such as CT, MRI, PET, DSA and so on. The most striking examples of them are the application of X ray computerized tomography (CT) and magnetic resonance imaging in the field of medical diagnosis. It can be predicted that magnetic resonance imaging (MRI) will definitely have more widespread prospects of applications and play more and more important role in clinical diagnosis looking forward to the development of image diagnostic technique for 21 st century. The authors also present the measuring methods for some parameters. The parameters described can be used for reference by clinical diagnosticians, operators on MRI and medical physicists who engages in image quality assurance (QA) and control (QC) in performing MRI acceptance test and routine test

Prenatal Genetic Diagnostic Tests

Science.gov (United States)

... are available for many inherited disorders. The main disadvantage is that diagnostic testing carries a very small ... chromosomes, arranged in order of size. Microarray: A technology that examines all of a person’s genes to ...

Childhood leukodystrophies: A literature review of updates on new definitions, classification, diagnostic approach and management.

Science.gov (United States)

Ashrafi, Mahmoud Reza; Tavasoli, Ali Reza

2017-05-01

Childhood leukodystrophies are a growing category of neurological disorders in pediatric neurology practice. With the help of new advanced genetic studies such as whole exome sequencing (WES) and whole genome sequencing (WGS), the list of childhood heritable white matter disorders has been increased to more than one hundred disorders. During the last three decades, the basic concepts and definitions, classification, diagnostic approach and medical management of these disorders much have changed. Pattern recognition based on brain magnetic resonance imaging (MRI), has played an important role in this process. We reviewed the last Global Leukodystrophy Initiative (GLIA) expert opinions in definition, new classification, diagnostic approach and medical management including emerging treatments for pediatric leukodystrophies. Copyright © 2017 The Japanese Society of Child Neurology. Published by Elsevier B.V. All rights reserved.

Diagnostic value of F18-FDG PET/CT in patients with the revised definition of fever of unknown origin

DEFF Research Database (Denmark)

Prakash, Vineet; Ketharanathan, Nagulabaskaran; Lorenz, Eleanor

2009-01-01

Objectives: Fever of unknown origin (FUO) is an increasingly accepted indication for PET/CT where it has a relatively high diagnostic yield. This study assesses its diagnostic value for the revised definition of FUO. Methods: The revised definition of FUO is fever of greater than 38.3C for more...... than 3 weeks duration and an uncertain diagnosis after comprehensive evaluation as an inpatient or outpatient for a minimum of 3 days or 3 outpatient visits, having excluded immunocompromised states. 59 patients (pts) (F=35, age 18-92) with this definition underwent PET with full diagnostic contrast......), neoplasm (6 pts) and drug fever (1 pt). Before ordering a PET/CT, conventional CT or MRI was performed in 43 pts. We considered that a PET/CT was essential to establish the final diagnosis in 15/43 pts (35%) with inconclusive CT or MRI. Conclusions: 18F-FDG PET/CT contributed to establishing a final...

Evaluating Diagnostic Point-of-Care Tests in Resource-Limited Settings

Science.gov (United States)

Drain, Paul K; Hyle, Emily P; Noubary, Farzad; Freedberg, Kenneth A; Wilson, Douglas; Bishai, William; Rodriguez, William; Bassett, Ingrid V

2014-01-01

Diagnostic point-of-care (POC) testing is intended to minimize the time to obtain a test result, thereby allowing clinicians and patients to make an expeditious clinical decision. As POC tests expand into resource-limited settings (RLS), the benefits must outweigh the costs. To optimize POC testing in RLS, diagnostic POC tests need rigorous evaluations focused on relevant clinical outcomes and operational costs, which differ from evaluations of conventional diagnostic tests. Here, we reviewed published studies on POC testing in RLS, and found no clearly defined metric for the clinical utility of POC testing. Therefore, we propose a framework for evaluating POC tests, and suggest and define the term “test efficacy” to describe a diagnostic test’s capacity to support a clinical decision within its operational context. We also proposed revised criteria for an ideal diagnostic POC test in resource-limited settings. Through systematic evaluations, comparisons between centralized diagnostic testing and novel POC technologies can be more formalized, and health officials can better determine which POC technologies represent valuable additions to their clinical programs. PMID:24332389

Yield and cost of individual common diagnostic tests in new primary care outpatients in Japan.

Science.gov (United States)

Takemura, Yuzuru; Ishida, Haku; Inoue, Yuji; Beck, J Robert

2002-01-01

Appropriate diagnostic testing involves considerations of cost-effectiveness. We examined the cost-effectiveness of individual tests in a panel of tests defined by the Japan Society of Clinical Pathology. We studied 540 new, symptomatic primary care outpatients with a set of 30 common diagnostic tests [the Essential Laboratory Tests (2); ELT(2) panel] for clinical evaluation and identification of occult disease. A useful result (UR) of testing was defined as a finding that contributed to a change in a physician's diagnosis or decision-making relating to a "tentative initial diagnosis" obtained from history and physical examination alone. The ELT(2) panel testing yielded 398 URs and uncovered 261 occult diseases among 540 patients. In total, 1592 tests contributed to either UR-generation or discovery of occult disease. The cost per effective test (cost required per test that contributed to either definition of effectiveness) ranged from 108 yen (approximately 0.92 US dollars) for total cholesterol to 6200 yen (approximately 52.50 dollars) for chest x-ray. Contribution rates and the cost per effective test varied among disease categories. We restructured panel components considering the effectiveness of each test. Subsets of the ELT(2) would have improved cost-effectiveness and achieved cost savings in five of eight disease categories. Assembly of tests based on cost-effectiveness can improve clinical efficiency and decrease total cost of panel testing for selected patient groups.

[Diagnostic test scale SI5: Assessment of sacroiliac joint dysfunction].

Science.gov (United States)

Acevedo González, Juan C; Quintero Oliveros, Silvia

2015-01-01

Sacroiliac joint dysfunction is a known cause of low back pain. We think that a diagnostic score scale (SI5) may be performed to assess diagnostic utility of clinical signs of sacroiliac joint dysfunction. The primary aim of the present study was to conduct the pilot study of our new diagnostic score scale, the SI5, for sacroiliac joint syndrome. We reviewed the literature on clinical characteristics, diagnostic tests and imaging most commonly used in diagnosing sacroiliac joint dysfunction. Our group evaluated the diagnostic utility of these aspects and we used those considered most representative to develop the SI5 diagnostic scale. The SI5 scale was applied to 22 patients with low back pain; afterwards, the standard test for diagnosing this pathology (selective blockage of the SI joint) was also performed on these patients. The sensitivity and specificity for each sign were also assessed and the diagnostic scale called SI5 was then proposed, based on these data. The most sensitive clinical tests for diagnosing SI joint dysfunction were 2 patient-reported clinical characteristics, the Laguerre Test, sacroiliac rocking test and Yeomans test (greater than 80% sensitivity). The tests with greatest diagnostic specificity (>80%) were the Lewitt test, Piedallu test and Gillet test. The proposed SI5 test score scale showed sensitivity of 73% and specificity of 71%. Sacroiliac joint syndrome has been shown to produce low back pain frequently; however, the diagnostic value of examination tests for sacroiliac joint pain has been questioned by other authors. The pilot study on the SI5 diagnostic score scale showed good sensitivity and specificity. However, the process of statistical validation of the SI5 needs to be continued. Copyright © 2014 Sociedad Española de Neurocirugía. Published by Elsevier España. All rights reserved.

Systematic reviews of diagnostic test accuracy

DEFF Research Database (Denmark)

Leeflang, Mariska M G; Deeks, Jonathan J; Gatsonis, Constantine

2008-01-01

More and more systematic reviews of diagnostic test accuracy studies are being published, but they can be methodologically challenging. In this paper, the authors present some of the recent developments in the methodology for conducting systematic reviews of diagnostic test accuracy studies....... Restrictive electronic search filters are discouraged, as is the use of summary quality scores. Methods for meta-analysis should take into account the paired nature of the estimates and their dependence on threshold. Authors of these reviews are advised to use the hierarchical summary receiver...

A review of the public health management of shigellosis in Australia in the era of culture-independent diagnostic testing.

Science.gov (United States)

Tai, Alex Y C; Easton, Marion; Encena, Jess; Rotty, Jessica; Valcanis, Mary; Howden, Benjamin P; Slota-Kan, Simon; Gregory, Joy

2016-12-01

To review the national case definition for shigellosis following the introduction of culture independent diagnostic testing by clinical laboratories and provide evidence to reform jurisdictional public health practices for the management shigellosis., . A review of all Australian jurisdictional public health guidelines for shigellosis was conducted. Victorian 2014 shigellosis data were analysed: demographics and risk factors for cases identified by conventional culture or culture-independent diagnostic methods were described. There was considerable variation in reporting of cases to the National Notifiable Disease Surveillance System (NNDSS) by the eight Australian jurisdictions, with an array of classifications based on diagnostic testing methodologies. Analysis of Victorian 2014 shigellosis data found that culture positive cases were more likely to have reported men who have sex with men (MSM) as a risk factor than PCR positive only cases (p<0.0001) and less likely to have reported overseas travel during their incubation period (p<0.0001). Over a 10-year period (2005 to 2014), only two of 86 cases who were employed in high-risk occupations had ongoing positive faecal cultures after appropriate treatment. The national surveillance case definition for shigellosis should be reviewed to facilitate standardised reporting across Australia. All jurisdictions must consider the public health significance of PCR positive only results in their surveillance risk assessments to inform management of shigellosis cases. © 2016 Public Health Association of Australia.

Development and Application of Diagnostic Test to Identify Students' Misconceptions of Quantum Physics

International Nuclear Information System (INIS)

Halim, A.A.; Meerah, T.S.; Lilia Halim

2009-01-01

A study on students' misconceptions on quantum physics is rarely being done, because the target audience is quite small. It is important to understand quantum physics concepts correctly especially for science students. This study was under taken to help students identify their misconceptions at the early stage. The aim of this study is to develop a diagnostic test which can access the students' misconceptions, and use the findings for the benefits of quantum physics courses. A multiple-choice Quantum Physics Diagnostic Test (QPDT), that involves concepts of light, atomic model, particle-wave dualism, wave function, and potential energy, was administered to 200 university students. The results shows that many students use the classical concepts to describe the quantum phenomenon. For example students describe light only as a wave, an electron only as a particle, and that the atomic structure is parallel to the solar system. To overcome these problems, it is suggested that lecturers spend more time in explaining the basic definitions and using analogies in quantum physics teaching. (author)

The definition, diagnostic testing, and management of chronic inducible urticarias - The EAACI/GA(2) LEN/EDF/UNEV consensus recommendations 2016 update and revision.

Science.gov (United States)

Magerl, M; Altrichter, S; Borzova, E; Giménez-Arnau, A; Grattan, C E H; Lawlor, F; Mathelier-Fusade, P; Meshkova, R Y; Zuberbier, T; Metz, M; Maurer, M

2016-06-01

These recommendations for the definition, diagnosis and management of chronic inducible urticaria (CIndU) extend, revise and update our previous consensus report on physical urticarias and cholinergic urticaria (Allergy, 2009). The aim of these recommendations is to improve the diagnosis and management of patients with CIndU. Our recommendations acknowledge the latest changes in our understanding of CIndU, and the available therapeutic options, as well as the development of novel diagnostic tools. © 2016 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Understanding the properties of diagnostic tests - Part 2: Likelihood ratios.

Science.gov (United States)

Ranganathan, Priya; Aggarwal, Rakesh

2018-01-01

Diagnostic tests are used to identify subjects with and without disease. In a previous article in this series, we examined some attributes of diagnostic tests - sensitivity, specificity, and predictive values. In this second article, we look at likelihood ratios, which are useful for the interpretation of diagnostic test results in everyday clinical practice.

[Diagnostic value of neuropsychological tests in mild cognitive impairment comorbid with Parkinson's disease].

Science.gov (United States)

Laskowska, Ilona; Koczorowski, Andrzej; Koziorowski, Dariusz; Gawryś, Ludwika

2014-01-01

Mild cognitive impairment (MCI) is present in on average one-fourth of Parkinson's disease (PD) patients with no dementia diagnosis. Only recently has PD-MCI been treated as a new diagnostic entity. In 2012, unified criteria were adopted which allow both diagnosing MCI in Parkinson's disease (PD-MCI) and further classification taking into account the profile of cognitive dysfunctions and the probability of evolution towards dementia. The diagnostic criteria were presented in the form of stipulations and guidelines assuming that diagnostic process is based on the neuropsychological assessment of the patient. The notion of MCI had been borrowed and for a couple of years had been relying on definitions developed in relation to Alzheimer's disease. For the first time, in the proposed criteria memory dysfunction is not the basis of classification. Only two categories of dysfunctions have been retained, single-domain and multiple-domain. Whether the adopted criteria will contribute to an accurate diagnosis of cognitive dysfunctions and PD-specific dementing processes remains an open question. In spite of some limitations, the presented criteria can certainly improve the efficacy of monitoring the patient's state at the same time allowing the hope for an appropriate therapy and a higher quality of life. Moreover, the unification of diagnostic criteria will be crucial in assessing usefulness ofneuropsychological test instruments as a basic method of investigating neurodegenerative processes not only in PD.

The indication area of a diagnostic test. Part I--discounting gain and loss in diagnostic certainty

NARCIS (Netherlands)

Stalpers, Lukas J. A.; Nelemans, Patty J.; Geurts, Sandra M. E.; Jansen, Erik; de Boer, Peter; Verbeek, André L. M.

2015-01-01

Test performance is conventionally expressed by gain in diagnostic certainty. We propose net diagnostic gain and indication area as more appropriate measures of test performance; then, the loss in certainty due to misclassification and the information of "no test" would be performed are taken into

Antimicrobial susceptibility testing by Australian veterinary diagnostic laboratories.

Science.gov (United States)

Hardefeldt, L Y; Marenda, M; Crabb, H; Stevenson, M A; Gilkerson, J R; Billman-Jacobe, H; Browning, G F

2018-04-01

The national strategy for tackling antimicrobial resistance highlights the need for antimicrobial stewardship in veterinary practice and for surveillance of antimicrobial susceptibility in veterinary pathogens. Diagnostic laboratories have an important role in facilitating both of these processes, but it is unclear whether data from veterinary diagnostic laboratories are similar enough to allow for compilation and if there is consistent promotion of appropriate antimicrobial use embedded in the approaches of different laboratories to susceptibility testing. A cross-sectional study of antimicrobial susceptibility testing and reporting procedures by Australian veterinary diagnostic laboratories was conducted in 2017 using an online questionnaire. All 18 veterinary diagnostic laboratories in Australia completed the questionnaire. Kirby-Bauer disc diffusion was the method predominantly used for antimicrobial susceptibility testing and was used to evaluate 86% of all isolates, although two different protocols were used across the 18 laboratories (CLSI 15/18, CDS 3/18). Minimum inhibitory concentrations were never reported by 61% of laboratories. Common isolates were consistently reported on across all species, except for gram-negative isolates in pigs, for which there was some variation in the approach to reporting. There was considerable diversity in the panels of antimicrobials used for susceptibility testing on common isolates and no consistency was apparent between laboratories for any bacterial species. We recommend that nationally agreed and consistent antimicrobial panels for routine susceptibility testing should be developed and a uniform set of guidelines should be adopted by veterinary diagnostic laboratories in Australia. © 2018 Australian Veterinary Association.

The impact of new trends in POCTs for companion diagnostics, non-invasive testing and molecular diagnostics.

Science.gov (United States)

Huckle, David

2015-06-01

Point-of-care diagnostics have been slowly developing over several decades and have taken on a new importance in current healthcare delivery for both diagnostics and development of new drugs. Molecular diagnostics have become a key driver of technology change and opened up new areas in companion diagnostics for use alongside pharmaceuticals and in new clinical approaches such as non-invasive testing. Future areas involving smartphone and other information technology advances, together with new developments in molecular biology, microfluidics and surface chemistry are adding to advances in the market. The focus for point-of-care tests with molecular diagnostic technologies is focused on advancing effective applications.

Immunochromatographic diagnostic test analysis using Google Glass.

Science.gov (United States)

Feng, Steve; Caire, Romain; Cortazar, Bingen; Turan, Mehmet; Wong, Andrew; Ozcan, Aydogan

2014-03-25

We demonstrate a Google Glass-based rapid diagnostic test (RDT) reader platform capable of qualitative and quantitative measurements of various lateral flow immunochromatographic assays and similar biomedical diagnostics tests. Using a custom-written Glass application and without any external hardware attachments, one or more RDTs labeled with Quick Response (QR) code identifiers are simultaneously imaged using the built-in camera of the Google Glass that is based on a hands-free and voice-controlled interface and digitally transmitted to a server for digital processing. The acquired JPEG images are automatically processed to locate all the RDTs and, for each RDT, to produce a quantitative diagnostic result, which is returned to the Google Glass (i.e., the user) and also stored on a central server along with the RDT image, QR code, and other related information (e.g., demographic data). The same server also provides a dynamic spatiotemporal map and real-time statistics for uploaded RDT results accessible through Internet browsers. We tested this Google Glass-based diagnostic platform using qualitative (i.e., yes/no) human immunodeficiency virus (HIV) and quantitative prostate-specific antigen (PSA) tests. For the quantitative RDTs, we measured activated tests at various concentrations ranging from 0 to 200 ng/mL for free and total PSA. This wearable RDT reader platform running on Google Glass combines a hands-free sensing and image capture interface with powerful servers running our custom image processing codes, and it can be quite useful for real-time spatiotemporal tracking of various diseases and personal medical conditions, providing a valuable tool for epidemiology and mobile health.

Clinical review: Distinguishing constitutional delay of growth and puberty from isolated hypogonadotropic hypogonadism: critical appraisal of available diagnostic tests.

Science.gov (United States)

Harrington, Jennifer; Palmert, Mark R

2012-09-01

Determining the etiology of delayed puberty during initial evaluation can be challenging. Specifically, clinicians often cannot distinguish constitutional delay of growth and puberty (CDGP) from isolated hypogonadotropic hypogonadism (IHH), with definitive diagnosis of IHH awaiting lack of spontaneous puberty by age 18 yr. However, the ability to make a timely, correct diagnosis has important clinical implications. The aim was to describe and evaluate the literature regarding the ability of diagnostic tests to distinguish CDGP from IHH. A PubMed search was performed using key words "puberty, delayed" and "hypogonadotropic hypogonadism," and citations within retrieved articles were reviewed to identify studies that assessed the utility of basal and stimulation tests in the diagnosis of delayed puberty. Emphasis was given to a test's ability to distinguish prepubertal adolescents with CDGP from those with IHH. Basal gonadotropin and GnRH stimulation tests have limited diagnostic specificity, with overlap in gonadotropin levels between adolescents with CDGP and IHH. Stimulation tests using more potent GnRH agonists and/or human chorionic gonadotropin may have better discriminatory value, but small study size, lack of replication of diagnostic thresholds, and prolonged protocols limit clinical application. A single inhibin B level in two recent studies demonstrated good differentiation between groups. Distinguishing IHH from CDGP is an important clinical issue. Basal inhibin B may offer a simple, discriminatory test if results from recent studies are replicated. However, current literature does not allow for recommendation of any diagnostic test for routine clinical use, making this an important area for future investigation.

Dilution testing using rapid diagnostic tests in a HIV diagnostic algorithm: a novel alternative for confirmation testing in resource limited settings.

Science.gov (United States)

Shanks, Leslie; Siddiqui, M Ruby; Abebe, Almaz; Piriou, Erwan; Pearce, Neil; Ariti, Cono; Masiga, Johnson; Muluneh, Libsework; Wazome, Joseph; Ritmeijer, Koert; Klarkowski, Derryck

2015-05-14

Current WHO testing guidelines for resource limited settings diagnose HIV on the basis of screening tests without a confirmation test due to cost constraints. This leads to a potential risk of false positive HIV diagnosis. In this paper, we evaluate the dilution test, a novel method for confirmation testing, which is simple, rapid, and low cost. The principle of the dilution test is to alter the sensitivity of a rapid diagnostic test (RDT) by dilution of the sample, in order to screen out the cross reacting antibodies responsible for falsely positive RDT results. Participants were recruited from two testing centres in Ethiopia where a tiebreaker algorithm using 3 different RDTs in series is used to diagnose HIV. All samples positive on the initial screening RDT and every 10th negative sample underwent testing with the gold standard and dilution test. Dilution testing was performed using Determine™ rapid diagnostic test at 6 different dilutions. Results were compared to the gold standard of Western Blot; where Western Blot was indeterminate, PCR testing determined the final result. 2895 samples were recruited to the study. 247 were positive for a prevalence of 8.5 % (247/2895). A total of 495 samples underwent dilution testing. The RDT diagnostic algorithm misclassified 18 samples as positive. Dilution at the level of 1/160 was able to correctly identify all these 18 false positives, but at a cost of a single false negative result (sensitivity 99.6 %, 95 % CI 97.8-100; specificity 100 %, 95 % CI: 98.5-100). Concordance between the gold standard and the 1/160 dilution strength was 99.8 %. This study provides proof of concept for a new, low cost method of confirming HIV diagnosis in resource-limited settings. It has potential for use as a supplementary test in a confirmatory algorithm, whereby double positive RDT results undergo dilution testing, with positive results confirming HIV infection. Negative results require nucleic acid testing to rule out false

Quantifying the Accuracy of a Diagnostic Test or Marker

NARCIS (Netherlands)

Linnet, Kristian; Bossuyt, Patrick M. M.; Moons, Karel G. M.; Reitsma, Johannes B. R.

2012-01-01

BACKGROUND: In recent years, increasing focus has been directed to the methodology for evaluating (new) tests or biomarkers. A key step in the evaluation of a diagnostic test is the investigation into its accuracy. CONTENT: We reviewed the literature on how to assess the accuracy of diagnostic

Local Sensitivity and Diagnostic Tests

NARCIS (Netherlands)

Magnus, J.R.; Vasnev, A.L.

2004-01-01

In this paper we confront sensitivity analysis with diagnostic testing.Every model is misspecified, but a model is useful if the parameters of interest (the focus) are not sensitive to small perturbations in the underlying assumptions. The study of the e ect of these violations on the focus is

DiagTest3Grp: An R Package for Analyzing Diagnostic Tests with Three Ordinal Groups

Directory of Open Access Journals (Sweden)

Jingqin Luo

2012-10-01

Full Text Available Medical researchers endeavor to identify potentially useful biomarkers to develop marker-based screening assays for disease diagnosis and prevention. Useful summary measures which properly evaluate the discriminative ability of diagnostic markers are critical for this purpose. Literature and existing software, for example, R packages nicely cover summary measures for diagnostic markers used for the binary case (e.g., healthy vs. diseased. An intermediate population at an early disease stage usually exists between the healthy and the fully diseased population in many disease processes. Supporting utilities for three-group diagnostic tests are highly desired and important for identifying patients at the early disease stage for timely treatments. However, application packages which provide summary measures for three ordinal groups are currently lacking. This paper focuses on two summary measures of diagnostic accuracy—volume under the receiver operating characteristic surface and the extended Youden index, with three diagnostic groups. We provide the R package DiagTest3Grp to estimate, under both parametric and nonparametric assumptions, the two summary measures and the associated variances, as well as the optimal cut-points for disease diagnosis. An omnibus test for multiple markers and a Wald test for two markers, on independent or paired samples, are incorporated to compare diagnostic accuracy across biomarkers. Sample size calculation under the normality assumption can be performed in the R package to design future diagnostic studies. A real world application evaluating the diagnostic accuracy of neuropsychological markers for Alzheimer’s disease is used to guide readers through step-by-step implementation of DiagTest3Grp to demonstrate its utility.

Whole Genome Sequencing Increases Molecular Diagnostic Yield Compared with Current Diagnostic Testing for Inherited Retinal Disease.

Science.gov (United States)

Ellingford, Jamie M; Barton, Stephanie; Bhaskar, Sanjeev; Williams, Simon G; Sergouniotis, Panagiotis I; O'Sullivan, James; Lamb, Janine A; Perveen, Rahat; Hall, Georgina; Newman, William G; Bishop, Paul N; Roberts, Stephen A; Leach, Rick; Tearle, Rick; Bayliss, Stuart; Ramsden, Simon C; Nemeth, Andrea H; Black, Graeme C M

2016-05-01

To compare the efficacy of whole genome sequencing (WGS) with targeted next-generation sequencing (NGS) in the diagnosis of inherited retinal disease (IRD). Case series. A total of 562 patients diagnosed with IRD. We performed a direct comparative analysis of current molecular diagnostics with WGS. We retrospectively reviewed the findings from a diagnostic NGS DNA test for 562 patients with IRD. A subset of 46 of 562 patients (encompassing potential clinical outcomes of diagnostic analysis) also underwent WGS, and we compared mutation detection rates and molecular diagnostic yields. In addition, we compared the sensitivity and specificity of the 2 techniques to identify known single nucleotide variants (SNVs) using 6 control samples with publically available genotype data. Diagnostic yield of genomic testing. Across known disease-causing genes, targeted NGS and WGS achieved similar levels of sensitivity and specificity for SNV detection. However, WGS also identified 14 clinically relevant genetic variants through WGS that had not been identified by NGS diagnostic testing for the 46 individuals with IRD. These variants included large deletions and variants in noncoding regions of the genome. Identification of these variants confirmed a molecular diagnosis of IRD for 11 of the 33 individuals referred for WGS who had not obtained a molecular diagnosis through targeted NGS testing. Weighted estimates, accounting for population structure, suggest that WGS methods could result in an overall 29% (95% confidence interval, 15-45) uplift in diagnostic yield. We show that WGS methods can detect disease-causing genetic variants missed by current NGS diagnostic methodologies for IRD and thereby demonstrate the clinical utility and additional value of WGS. Copyright © 2016 American Academy of Ophthalmology. Published by Elsevier Inc. All rights reserved.

Evaluation of surveillance case definition in the diagnosis of leptospirosis, using the Microscopic Agglutination Test: a validation study.

Science.gov (United States)

Dassanayake, Dinesh L B; Wimalaratna, Harith; Agampodi, Suneth B; Liyanapathirana, Veranja C; Piyarathna, Thibbotumunuwe A C L; Goonapienuwala, Bimba L

2009-04-22

Leptospirosis is endemic in both urban and rural areas of Sri Lanka and there had been many out breaks in the recent past. This study was aimed at validating the leptospirosis surveillance case definition, using the Microscopic Agglutination Test (MAT). The study population consisted of patients with undiagnosed acute febrile illness who were admitted to the medical wards of the Teaching Hospital Kandy, from 1st July 2007 to 31st July 2008. The subjects were screened to diagnose leptospirosis according to the leptospirosis case definition. MAT was performed on blood samples taken from each patient on the 7th day of fever. Leptospirosis case definition was evaluated in regard to sensitivity, specificity and predictive values, using a MAT titre >or= 1:800 for confirming leptospirosis. A total of 123 patients were initially recruited of which 73 had clinical features compatible with the surveillance case definition. Out of the 73 only 57 had a positive MAT result (true positives) leaving 16 as false positives. Out of the 50 who didn't have clinical features compatible with the case definition 45 had a negative MAT as well (true negatives), therefore 5 were false negatives. Total number of MAT positives was 62 out of 123. According to these results the test sensitivity was 91.94%, specificity 73.77%, positive predictive value and negative predictive values were 78.08% and 90% respectively. Diagnostic accuracy of the test was 82.93%. This study confirms that the surveillance case definition has a very high sensitivity and negative predictive value with an average specificity in diagnosing leptospirosis, based on a MAT titre of >or= 1: 800.

Cetrorelix suppression test in the diagnostic work-up of severe hyperandrogenism in adolescence.

NARCIS (Netherlands)

Man, M. de; Derksen, E.; Pieters, G.F.F.M.; Boer, H. de

2008-01-01

Conventional diagnostic procedures failed to provide a definitive diagnosis in a 15 year-old girl presenting with severe hirsutism, oligomenorrhea, and markedly elevated serum testosterone levels. To examine whether androgen overproduction was luteinizing hormone (LH) dependent and thus likely of

Reporting Diagnostic Scores in Educational Testing: Temptations, Pitfalls, and Some Solutions

Science.gov (United States)

Sinharay, Sandip; Puhan, Gautam; Haberman, Shelby J.

2010-01-01

Diagnostic scores are of increasing interest in educational testing due to their potential remedial and instructional benefit. Naturally, the number of educational tests that report diagnostic scores is on the rise, as are the number of research publications on such scores. This article provides a critical evaluation of diagnostic score reporting…

Automation of diagnostic genetic testing: mutation detection by cyclic minisequencing.

Science.gov (United States)

Alagrund, Katariina; Orpana, Arto K

2014-01-01

The rising role of nucleic acid testing in clinical decision making is creating a need for efficient and automated diagnostic nucleic acid test platforms. Clinical use of nucleic acid testing sets demands for shorter turnaround times (TATs), lower production costs and robust, reliable methods that can easily adopt new test panels and is able to run rare tests in random access principle. Here we present a novel home-brew laboratory automation platform for diagnostic mutation testing. This platform is based on the cyclic minisequecing (cMS) and two color near-infrared (NIR) detection. Pipetting is automated using Tecan Freedom EVO pipetting robots and all assays are performed in 384-well micro plate format. The automation platform includes a data processing system, controlling all procedures, and automated patient result reporting to the hospital information system. We have found automated cMS a reliable, inexpensive and robust method for nucleic acid testing for a wide variety of diagnostic tests. The platform is currently in clinical use for over 80 mutations or polymorphisms. Additionally to tests performed from blood samples, the system performs also epigenetic test for the methylation of the MGMT gene promoter, and companion diagnostic tests for analysis of KRAS and BRAF gene mutations from formalin fixed and paraffin embedded tumor samples. Automation of genetic test reporting is found reliable and efficient decreasing the work load of academic personnel.

A web-based test of residents' skills in diagnostic radiology

International Nuclear Information System (INIS)

Finlay, K.; Norman, G.R.; Keane, D.R.; Stolberg, H.

2006-01-01

To develop an objective, Web-based tool for evaluating residents' knowledge of diagnostic radiology. We developed and tested a Web-based evaluation tool (the Diagnostic Radiology Skills Test) that consists of 3 tests, one in each of 3 domains of diagnostic radiology: chest, gastrointestinal, and musculoskeletal imaging. Each test comprises 30 cases representing a range of difficulty in the domain, including normal states, normal variants, typical cases of common diagnoses, and cases with more subtle findings. Cases are presented with a long menu of domain-specific possible diagnoses (response options), each coded for diagnostic appropriateness. Our subjects were 21 residents in postgraduate year (PGY) 2 to 5 and 11 experts in diagnostic radiology. Subjects accessed the tool via a Web site on our Web server. Residents test results were compared for reliability and validity across domain, case, and training level. In addition, results were correlated with commonly used established and objective evaluation tools. The tool demonstrated consistent monotonic improvement in performance with training level. It showed acceptable reliability in discriminating between residents at different performance levels, both within and across training levels (r = 0.53 within level and 0.69 across levels). Test results also had concurrent validity against the American College of Radiology In-Training Examination, a widely accepted objective assessment tool (r = 0.65, P < 0.01), and 2 Objective Structured Clinical Examinations (OSCEs) focusing on diagnostic skills (r = 0.78 and r 0.69, P < 0.01, respectively). Our study demonstrates the feasibility of a Web-based, standardized, objective assessment method for evaluating residents' performance. (author)

Predictors of Inappropriate Use of Diagnostic Tests and Management of Bronchiolitis

Science.gov (United States)

Sarmiento, Lorena; Rojas-Soto, Gladys E.

2017-01-01

Background The aim of the present study was to determine predictors of inappropriate use of diagnostic tests and management of bronchiolitis in a population of hospitalized infants. Methods In an analytical cross-sectional study, we determined independent predictors of the inappropriate use of diagnostic tests and management of bronchiolitis in a population of hospitalized infants. We defined a composite outcome score as the main outcome variable. Results Of the 303 included patients, 216 (71.3%) experienced an inappropriate use of diagnostic tests and treatment of bronchiolitis. After controlling for potential confounders, it was found that atopic dermatitis (OR 5.30; CI 95% 1.14–24.79; p = 0.034), length of hospital stay (OR 1.48; CI 95% 1.08–2.03; p = 0.015), and the number of siblings (OR 1.92; CI 95% 1.13–3.26; p = 0.015) were independent predictors of an inappropriate use of diagnostic tests and treatment of the disease. Conclusions Inappropriate use of diagnostic tests and treatment of bronchiolitis was a highly prevalent outcome in our population of study. Participants with atopic dermatitis, a longer hospital stay, and a greater number of siblings were at increased risk for inappropriate use of diagnostic tests and management of the disease. PMID:28758127

The definitive diagnostic process and successful treatment for ABPM caused by Schizophyllum commune: a report of two cases.

Science.gov (United States)

Ogawa, Haruhiko; Fujimura, Masaki; Takeuchi, Yasuo; Makimura, Koichi; Satoh, Kazuo

2012-03-01

Although mucoid impaction of the bronchi (MIB) is a well-known manifestation in allergic bronchopulmonary mycosis (ABPM), when unknown samples or plural eumycetes are cultured from bronchial materials, several problems are encountered which can affect the definitive diagnostic process or successful treatment. The definitive diagnostic process of two patients [a 58-(Case 1) and a 70-(Case 2) year-old female] with MIB was: 1) to identify the existence of any allergic respiratory disorder, 2) to detect the fungi obtained from bronchial materials, with use of the 28S rDNA sequencing and analysis, 3) to investigate whether the detected fungus was a probable etiologic antigen, and 4) to make the final diagnosis based on the results of the inhalation examinations using the antigenic solution of the fungi. As a treatment strategy, bronchial toilet and low dose itraconazole therapy were planned according to the clinical manifestations of each patient. The two patients with MIB were successfully diagnosed as ABPM caused by Schizophyllum commune (Sc-ABPM) accompanied with hyperattenuating mucoid impaction. The reliability of some allergological makers as a substitution for the bronchoprovocation test should be clarified in near future. Clinical manifestations demonstrated in our cases suggested that the allergic reaction such as eosinophilic bronchoalveolitis spreading around the mucus plug was a primary lesion underlying the Sc-ABPM. The success of the treatment for Sc-ABPM will be achieved by the strategy targeting to fundamental condition and by the control of the disease recurrence by means of effective environmental management.

Optimal Combinations of Diagnostic Tests Based on AUC.

Science.gov (United States)

Huang, Xin; Qin, Gengsheng; Fang, Yixin

2011-06-01

When several diagnostic tests are available, one can combine them to achieve better diagnostic accuracy. This article considers the optimal linear combination that maximizes the area under the receiver operating characteristic curve (AUC); the estimates of the combination's coefficients can be obtained via a nonparametric procedure. However, for estimating the AUC associated with the estimated coefficients, the apparent estimation by re-substitution is too optimistic. To adjust for the upward bias, several methods are proposed. Among them the cross-validation approach is especially advocated, and an approximated cross-validation is developed to reduce the computational cost. Furthermore, these proposed methods can be applied for variable selection to select important diagnostic tests. The proposed methods are examined through simulation studies and applications to three real examples. © 2010, The International Biometric Society.

Improving prescribing practices with rapid diagnostic tests (RDTs)

DEFF Research Database (Denmark)

Burchett, Helen E D; Leurent, Baptiste; Baiden, Frank

2017-01-01

OBJECTIVES: The overuse of antimalarial drugs is widespread. Effective methods to improve prescribing practice remain unclear. We evaluated the impact of 10 interventions that introduced rapid diagnostic tests for malaria (mRDTs) on the use of tests and adherence to results in different contexts...... packages, supervision, supplies and community sensitisation. OUTCOME MEASURES: Analysis explored variation in: (1) uptake of mRDTs (% febrile patients tested); (2) provider adherence to positive mRDTs (% Plasmodium falciparum positive prescribed/given Artemisinin Combination Treatment); (3) provider...... characteristics fitted with their own priorities. Goodness of fit of mRDTs with existing consultation and diagnostic practices appeared crucial to maximising the impact of mRDTs on care, as did prior familiarity with malaria testing; adequate human resources and supplies; possible alternative treatments for m...

Drug sensitivity testing platforms for gastric cancer diagnostics.

Science.gov (United States)

Lau, Vianne; Wong, Andrea Li-Ann; Ng, Christopher; Mok, Yingting; Lakshmanan, Manikandan; Yan, Benedict

2016-02-01

Gastric cancer diagnostics has traditionally been histomorphological and primarily the domain of surgical pathologists. Although there is an increasing usage of molecular and genomic techniques for clinical diagnostics, there is an emerging field of personalised drug sensitivity testing. In this review, we describe the various personalised drug sensitivity testing platforms and discuss the challenges facing clinical adoption of these assays for gastric cancer. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/

Nonparametric predictive inference for combining diagnostic tests with parametric copula

Science.gov (United States)

Muhammad, Noryanti; Coolen, F. P. A.; Coolen-Maturi, T.

2017-09-01

Measuring the accuracy of diagnostic tests is crucial in many application areas including medicine and health care. The Receiver Operating Characteristic (ROC) curve is a popular statistical tool for describing the performance of diagnostic tests. The area under the ROC curve (AUC) is often used as a measure of the overall performance of the diagnostic test. In this paper, we interest in developing strategies for combining test results in order to increase the diagnostic accuracy. We introduce nonparametric predictive inference (NPI) for combining two diagnostic test results with considering dependence structure using parametric copula. NPI is a frequentist statistical framework for inference on a future observation based on past data observations. NPI uses lower and upper probabilities to quantify uncertainty and is based on only a few modelling assumptions. While copula is a well-known statistical concept for modelling dependence of random variables. A copula is a joint distribution function whose marginals are all uniformly distributed and it can be used to model the dependence separately from the marginal distributions. In this research, we estimate the copula density using a parametric method which is maximum likelihood estimator (MLE). We investigate the performance of this proposed method via data sets from the literature and discuss results to show how our method performs for different family of copulas. Finally, we briefly outline related challenges and opportunities for future research.

ITER diagnostics: Maintenance and commissioning in the hot cell test bed

International Nuclear Information System (INIS)

Walker, C.I.; Barnsley, R.; Costley, A.E.; Gottfried, R.; Haist, B.; Itami, K.; Kondoh, T.; Loesser, G.D.; Palmer, J.; Sugie, T.; Tesini, A.; Vayakis, G.

2005-01-01

In-vessel diagnostic equipment in ITER integrated in six equatorial and 12 upper ports, 16 divertor cassettes and five lower ports is designed to be removed in modules and then repaired, tested and commissioned in the same location at the ITER hot cell. The repair requirements and tests on these components are described along with design features that facilitate repair. The testing establishes the repair strategy, qualifies the refurbishment work and finally checks the mechanical and diagnostic function before the return of the modules. At the hot cell, a dummy port is provided for tests of mechanical and vacuum integrity as well as commissioning of the diagnostic equipment. The scope of the hot cell maintenance and commissioning activities is summarised and an overview of the integration of the diagnostic equipment is given

Molecular diagnostics clinical utility strategy: a six-part framework.

Science.gov (United States)

Frueh, Felix W; Quinn, Bruce

2014-09-01

The clinical utility of a molecular test rises proportional to a favorable regulatory risk/benefit assessment, and clinical utility is the driver of payer coverage decisions. Although a great deal has been written about clinical utility, debates still center on its 'definition.' We argue that the definition (an impact on clinical outcomes) is self-evident, and improved communications should focus on sequential steps in building and proving an adequate level of confidence for the diagnostic test's clinical value proposition. We propose a six-part framework to facilitate communications between test developers and health technology evaluators, relevant to both regulatory and payer decisions.

A REVIEW ON DIAGNOSTIC TECHNIQUES FOR BRUCELLOSIS

African Journals Online (AJOL)

User

2014-01-01

Jan 1, 2014 ... Brucellosis presents with many clinical manifestation that make its diagnosis a difficult task. Ever since the report of the first serologic test for brucellosis, a definitive diagnostic technique has been actively pursued. The most widely used methods of diagnosis are based on serology, which measures the.

Diagnostic reliability of MMPI-2 computer-based test interpretations.

Science.gov (United States)

Pant, Hina; McCabe, Brian J; Deskovitz, Mark A; Weed, Nathan C; Williams, John E

2014-09-01

Reflecting the common use of the MMPI-2 to provide diagnostic considerations, computer-based test interpretations (CBTIs) also typically offer diagnostic suggestions. However, these diagnostic suggestions can sometimes be shown to vary widely across different CBTI programs even for identical MMPI-2 profiles. The present study evaluated the diagnostic reliability of 6 commercially available CBTIs using a 20-item Q-sort task developed for this study. Four raters each sorted diagnostic classifications based on these 6 CBTI reports for 20 MMPI-2 profiles. Two questions were addressed. First, do users of CBTIs understand the diagnostic information contained within the reports similarly? Overall, diagnostic sorts of the CBTIs showed moderate inter-interpreter diagnostic reliability (mean r = .56), with sorts for the 1/2/3 profile showing the highest inter-interpreter diagnostic reliability (mean r = .67). Second, do different CBTIs programs vary with respect to diagnostic suggestions? It was found that diagnostic sorts of the CBTIs had a mean inter-CBTI diagnostic reliability of r = .56, indicating moderate but not strong agreement across CBTIs in terms of diagnostic suggestions. The strongest inter-CBTI diagnostic agreement was found for sorts of the 1/2/3 profile CBTIs (mean r = .71). Limitations and future directions are discussed. PsycINFO Database Record (c) 2014 APA, all rights reserved.

A diagnostic test for apraxia in stroke patients: internal consistency and diagnostic value.

NARCIS (Netherlands)

Heugten, C.M. van; Dekker, J.; Deelman, B.G.; Stehmann-Saris, F.C.; Kinebanian, A.

1999-01-01

The internal consistency and the diagnostic value of a test for apraxia in patients having had a stroke are presented. Results indicate that the items of the test form a strong and consistent scale: Cronbach's alpha as well as the results of a Mokken scale analysis present good reliability and good

Analysis of the Astronomy Diagnostic Test

Science.gov (United States)

Brogt, Erik; Sabers, Darrell; Prather, Edward E.; Deming, Grace L.; Hufnagel, Beth; Slater, Timothy F.

2007-01-01

Seventy undergraduate class sections were examined from the database of Astronomy Diagnostic Test (ADT) results of Deming and Hufnagel to determine if course format correlated with ADT normalized gain scores. Normalized gains were calculated for four different classroom scenarios: lecture, lecture with discussion, lecture with lab, and lecture…

Diagnostic development and support of MHD test facilities

Energy Technology Data Exchange (ETDEWEB)

1990-01-01

The Diagnostic Instrumentation and Analysis Laboratory (DIAL) at Mississippi State University (MSU) is developing diagnostic instruments for MHD power train data acquisition and for support of MHD component development test facilities. Microprocessor-controlled optical instruments, initially developed for Heat Recovery/Seed Recovery support, are being refined, and new systems to measure temperatures and gas-seed-slag stream characteristics are being developed. To further data acquisition and analysis capabilities, the diagnostic systems are being interfaced with DIAL's computers. Technical support for the diagnostic needs of the national MHD research effort is being provided. DIAL personnel will also cooperate with government agencies and private industries to improve the transformation of research and development results into processes, products and services applicable to their needs. 25 figs., 6 tabs.

Diagnostic development and support of MHD test facilities

International Nuclear Information System (INIS)

Shepard, W.S.; Cook, R.L.

1990-01-01

The Diagnostic Instrumentation and Analysis Laboratory (DIAL) at Mississippi State University (MSU) is developing diagnostic instruments for MHD power train data acquisition and for support of MHD component development test facilities. Microprocessor-controlled optical instruments, initially developed for Heat Recovery/ Seed Recovery support, are being refined, and new systems to measure temperatures and gas-seed-slag stream characteristics are being developed. To further data acquisition and analysis capabilities, the diagnostic systems are being interfaced with DIAL's computers. Technical support for the diagnostic needs of the national MHD research effort is being provided. DIAL personnel will also cooperate with government agencies and private industries to improve the transformation of research and development results into processes, products and services applicable to their needs

Diagnostic and Therapeutic Management of a First Unprovoked Seizure in Children and Adolescents With a Focus on the Revised Diagnostic Criteria for Epilepsy.

Science.gov (United States)

Sansevere, Arnold J; Avalone, Jennifer; Strauss, Lauren Doyle; Patel, Archana A; Pinto, Anna; Ramachandran, Maya; Fernandez, Ivan Sanchez; Bergin, Ann M; Kimia, Amir; Pearl, Phillip L; Loddenkemper, Tobias

2017-07-01

By definition, unprovoked seizures are not precipitated by an identifiable factor, such as fever or trauma. A thorough history and physical examination are essential to caring for pediatric patients with a potential first unprovoked seizure. Differential diagnosis, EEG, neuroimaging, laboratory tests, and initiation of treatment will be reviewed. Treatment is typically initiated after 2 unprovoked seizures, or after 1 seizure in select patients with distinct epilepsy syndromes. Recent expansion of the definition of epilepsy by the ILAE allows for the diagnosis of epilepsy to be made after the first seizure if the clinical presentation and supporting diagnostic studies suggest a greater than 60% chance of a second seizure. This review summarizes the current literature on the diagnostic and therapeutic management of first unprovoked seizure in children and adolescents while taking into consideration the revised diagnostic criteria of epilepsy.

9 CFR 147.8 - Procedures for preparing egg yolk samples for diagnostic tests.

Science.gov (United States)

2010-01-01

... samples for diagnostic tests. 147.8 Section 147.8 Animals and Animal Products ANIMAL AND PLANT HEALTH... IMPROVEMENT PLAN Blood Testing Procedures § 147.8 Procedures for preparing egg yolk samples for diagnostic... for diagnostic testing. (b) The authorized laboratory must identify each egg as to the breeding flock...

Rapid diagnostic tests for typhoid and paratyphoid (enteric) fever.

Science.gov (United States)

Wijedoru, Lalith; Mallett, Sue; Parry, Christopher M

2017-05-26

Differentiating both typhoid (Salmonella Typhi) and paratyphoid (Salmonella Paratyphi A) infection from other causes of fever in endemic areas is a diagnostic challenge. Although commercial point-of-care rapid diagnostic tests (RDTs) for enteric fever are available as alternatives to the current reference standard test of blood or bone marrow culture, or to the widely used Widal Test, their diagnostic accuracy is unclear. If accurate, they could potentially replace blood culture as the World Health Organization (WHO)-recommended main diagnostic test for enteric fever. To assess the diagnostic accuracy of commercially available rapid diagnostic tests (RDTs) and prototypes for detecting Salmonella Typhi or Paratyphi A infection in symptomatic persons living in endemic areas. We searched the Cochrane Infectious Diseases Group Specialized Register, MEDLINE, Embase, Science Citation Index, IndMED, African Index Medicus, LILACS, ClinicalTrials.gov, and the World Health Organization (WHO) International Clinical Trials Registry Platform (ICTRP) up to 4 March 2016. We manually searched WHO reports, and papers from international conferences on Salmonella infections. We also contacted test manufacturers to identify studies. We included diagnostic accuracy studies of enteric fever RDTs in patients with fever or with symptoms suggestive of enteric fever living in endemic areas. We classified the reference standard used as either Grade 1 (result from a blood culture and a bone marrow culture) or Grade 2 (result from blood culture and blood polymerase chain reaction, or from blood culture alone). Two review authors independently extracted the test result data. We used a modified QUADAS-2 extraction form to assess methodological quality. We performed a meta-analysis when there were sufficient studies for the test and heterogeneity was reasonable. Thirty-seven studies met the inclusion criteria and included a total of 5080 participants (range 50 to 1732). Enteric fever prevalence

Antiphospholipid Syndrome Laboratory Testing and Diagnostic Strategies

Science.gov (United States)

Ortel, Thomas L.

2016-01-01

The Antiphospholipid Syndrome (APS) is diagnosed in patients with recurrent thromboembolic events and/or pregnancy loss in the presence of persistent laboratory evidence for antiphospholipid antibodies. Diagnostic tests for the detection of antiphospholipid antibodies include laboratory assays that detect anticardiolipin antibodies, lupus anticoagulants, and anti-β2-glycoprotein I antibodies. These assays have their origins beginning more than sixty years ago, with the identification of the biologic false positive test for syphilis, the observation of ‘circulating anticoagulants’ in certain patients with systemic lupus erythematosus, the identification of cardiolipin as a key component in the serologic test for syphilis, and the recognition and characterization of a ‘cofactor’ for antibody binding to phospholipids. Although these assays have been used clinically for many years, there are still problems with the accurate diagnosis of patients with this syndrome. For example, lupus anticoagulant testing can be difficult to interpret in patients receiving anticoagulant therapy, but most patients with a thromboembolic event will already be anticoagulated before the decision to perform the tests has been made. In addition to understanding limitations of the assays, clinicians also need to be aware of which patients should be tested and not obtain testing on patients unlikely to have APS. New tests and diagnostic strategies are in various stages of development and should help improve our ability to accurately diagnose this important clinical disorder. PMID:22473619

30 CFR 250.522 - When do I have to repeat casing diagnostic testing?

Science.gov (United States)

2010-07-01

... 30 Mineral Resources 2 2010-07-01 2010-07-01 false When do I have to repeat casing diagnostic... Operations Casing Pressure Management § 250.522 When do I have to repeat casing diagnostic testing? Casing diagnostic testing must be repeated according to the following table: When * * * you must repeat diagnostic...

More Than Just Accuracy: A Novel Method to Incorporate Multiple Test Attributes in Evaluating Diagnostic Tests Including Point of Care Tests.

Science.gov (United States)

Thompson, Matthew; Weigl, Bernhard; Fitzpatrick, Annette; Ide, Nicole

2016-01-01

Current frameworks for evaluating diagnostic tests are constrained by a focus on diagnostic accuracy, and assume that all aspects of the testing process and test attributes are discrete and equally important. Determining the balance between the benefits and harms associated with new or existing tests has been overlooked. Yet, this is critically important information for stakeholders involved in developing, testing, and implementing tests. This is particularly important for point of care tests (POCTs) where tradeoffs exist between numerous aspects of the testing process and test attributes. We developed a new model that multiple stakeholders (e.g., clinicians, patients, researchers, test developers, industry, regulators, and health care funders) can use to visualize the multiple attributes of tests, the interactions that occur between these attributes, and their impacts on health outcomes. We use multiple examples to illustrate interactions between test attributes (test availability, test experience, and test results) and outcomes, including several POCTs. The model could be used to prioritize research and development efforts, and inform regulatory submissions for new diagnostics. It could potentially provide a way to incorporate the relative weights that various subgroups or clinical settings might place on different test attributes. Our model provides a novel way that multiple stakeholders can use to visualize test attributes, their interactions, and impacts on individual and population outcomes. We anticipate that this will facilitate more informed decision making around diagnostic tests.

Molecular Diagnostic Tests for Microsporidia

Directory of Open Access Journals (Sweden)

Kaya Ghosh

2009-01-01

Full Text Available The Microsporidia are a ubiquitous group of eukaryotic obligate intracellular parasites which were recognized over 100 years ago with the description of Nosema bombycis, a parasite of silkworms. It is now appreciated that these organisms are related to the Fungi. Microsporidia infect all major animal groups most often as gastrointestinal pathogens; however they have been reported from every tissue and organ, and their spores are common in environmental sources such as ditch water. Several different genera of these organisms infect humans, but the majority of infections are due to either Enterocytozoon bieneusi or Encephalitozoon species. These pathogens can be difficult to diagnose, but significant progress has been made in the last decade in the development of molecular diagnostic reagents for these organisms. This report reviews the molecular diagnostic tests that have been described for the identification of the microsporidia that infect humans.

Network meta-analysis of diagnostic test accuracy studies identifies and ranks the optimal diagnostic tests and thresholds for health care policy and decision-making.

Science.gov (United States)

Owen, Rhiannon K; Cooper, Nicola J; Quinn, Terence J; Lees, Rosalind; Sutton, Alex J

2018-07-01

Network meta-analyses (NMA) have extensively been used to compare the effectiveness of multiple interventions for health care policy and decision-making. However, methods for evaluating the performance of multiple diagnostic tests are less established. In a decision-making context, we are often interested in comparing and ranking the performance of multiple diagnostic tests, at varying levels of test thresholds, in one simultaneous analysis. Motivated by an example of cognitive impairment diagnosis following stroke, we synthesized data from 13 studies assessing the efficiency of two diagnostic tests: Mini-Mental State Examination (MMSE) and Montreal Cognitive Assessment (MoCA), at two test thresholds: MMSE accounting for the correlations between multiple test accuracy measures from the same study. We developed and successfully fitted a model comparing multiple tests/threshold combinations while imposing threshold constraints. Using this model, we found that MoCA at threshold decision making. Copyright © 2018 The Authors. Published by Elsevier Inc. All rights reserved.

Efficient strategies to find diagnostic test accuracy studies in kidney journals.

Science.gov (United States)

Rogerson, Thomas E; Ladhani, Maleeka; Mitchell, Ruth; Craig, Jonathan C; Webster, Angela C

2015-08-01

Nephrologists looking for quick answers to diagnostic clinical questions in MEDLINE can use a range of published search strategies or Clinical Query limits to improve the precision of their searches. We aimed to evaluate existing search strategies for finding diagnostic test accuracy studies in nephrology journals. We assessed the accuracy of 14 search strategies for retrieving diagnostic test accuracy studies from three nephrology journals indexed in MEDLINE. Two investigators hand searched the same journals to create a reference set of diagnostic test accuracy studies to compare search strategy results against. We identified 103 diagnostic test accuracy studies, accounting for 2.1% of all studies published. The most specific search strategy was the Narrow Clinical Queries limit (sensitivity: 0.20, 95% CI 0.13-0.29; specificity: 0.99, 95% CI 0.99-0.99). Using the Narrow Clinical Queries limit, a searcher would need to screen three (95% CI 2-6) articles to find one diagnostic study. The most sensitive search strategy was van der Weijden 1999 Extended (sensitivity: 0.95; 95% CI 0.89-0.98; specificity 0.55, 95% CI 0.53-0.56) but required a searcher to screen 24 (95% CI 23-26) articles to find one diagnostic study. Bachmann 2002 was the best balanced search strategy, which was sensitive (0.88, 95% CI 0.81-0.94), but also specific (0.74, 95% CI 0.73-0.75), with a number needed to screen of 15 (95% CI 14-17). Diagnostic studies are infrequently published in nephrology journals. The addition of a strategy for diagnostic studies to a subject search strategy in MEDLINE may reduce the records needed to screen while preserving adequate search sensitivity for routine clinical use. © 2015 Asian Pacific Society of Nephrology.

Characterization of the Goubau line for testing beam diagnostic instruments

Science.gov (United States)

Kim, S. Y.; Stulle, F.; Sung, C. K.; Yoo, K. H.; Seok, J.; Moon, K. J.; Choi, C. U.; Chung, Y.; Kim, G.; Woo, H. J.; Kwon, J.; Lee, I. G.; Choi, E. M.; Chung, M.

2017-12-01

One of the main characteristics of the Goubau line is that it supports a low-loss, non-radiated surface wave guided by a dielectric-coated metal wire. The dominant mode of the surface wave along the Goubau line is a TM01 mode, which resembles the pattern of the electromagnetic fields induced in the metallic beam pipe when the charged particle beam passes through it. Therefore, the Goubau line can be used for the preliminary bench test and performance optimization of the beam diagnostic instruments without requiring charged particle beams from the accelerators. In this paper, we discuss the basic properties of the Goubau line for testing beam diagnostic instruments and present the initial test results for button-type beam position monitors (BPMs). The experimental results are consistent with the theoretical estimations, which indicates that Goubau line allows effective testing of beam diagnostic equipment.

Better Tests, Better Care: Improved Diagnostics for Infectious Diseases

Science.gov (United States)

Caliendo, Angela M.; Gilbert, David N.; Ginocchio, Christine C.; Hanson, Kimberly E.; May, Larissa; Quinn, Thomas C.; Tenover, Fred C.; Alland, David; Blaschke, Anne J.; Bonomo, Robert A.; Carroll, Karen C.; Ferraro, Mary Jane; Hirschhorn, Lisa R.; Joseph, W. Patrick; Karchmer, Tobi; MacIntyre, Ann T.; Reller, L. Barth; Jackson, Audrey F.

2013-01-01

In this IDSA policy paper, we review the current diagnostic landscape, including unmet needs and emerging technologies, and assess the challenges to the development and clinical integration of improved tests. To fulfill the promise of emerging diagnostics, IDSA presents recommendations that address a host of identified barriers. Achieving these goals will require the engagement and coordination of a number of stakeholders, including Congress, funding and regulatory bodies, public health agencies, the diagnostics industry, healthcare systems, professional societies, and individual clinicians. PMID:24200831

Diagnostic accuracy of the Rivalta test for feline infectious peritonitis.

Science.gov (United States)

Fischer, Yvonne; Sauter-Louis, Carola; Hartmann, Katrin

2012-12-01

The Rivalta test has been used routinely in Europe to diagnose feline infectious peritonitis (FIP) in cats with effusions, but its diagnostic accuracy is uncertain. The objectives of this study were to calculate sensitivity, specificity, and positive (PPV) and negative (NPV) predictive values of the Rivalta test for FIP and to identify correlations between a positive Rivalta test and variables measured in effusion fluid and peripheral blood. In this retrospective study, medical records of cats with effusions were reviewed, and cats with conclusive results for the Rivalta test were included. The prevalence of FIP in this population was determined, and sensitivity, specificity, and PPV and NPV of the Rivalta test were calculated. Variables measured in effusion fluid and peripheral blood were compared between cats that had positive or negative Rivalta tests using the Mann-Whitney U-test and multivariate analysis. Of 851 cats with effusions, 782 had conclusively positive or negative results for the Rivalta test. A definitive final diagnosis was made in 497 of these cats. Prevalence of FIP in cats with effusion and a conclusive Rivalta test result was 34.6%. The Rivalta test had a sensitivity of 91.3%, specificity of 65.5%, PPV of 58.4%, and NPV of 93.4% for the diagnosis of FIP. These values increased when cats with lymphoma or bacterial infections were excluded, or when only cats ≤ 2 years were considered. Increased effusion cholesterol concentration and specific gravity as well as decreased serum albumin:globulin ratio and hyperbilirubinemia were positively correlated with positive Rivalta test results. Sensitivity, specificity, and PPV of the Rivalta test for the diagnosis of FIP were lower than previously reported except when used in young cats. The components in effusions that lead to a positive Rivalta test remain unknown, but the positivity is not simply related to high total protein concentration. © 2012 American Society for Veterinary Clinical Pathology.

Diabetic neuropathies: update on definitions, diagnostic criteria, estimation of severity, and treatments

DEFF Research Database (Denmark)

Tesfaye, Solomon; Boulton, Andrew J M; Dyck, Peter J

2010-01-01

Preceding the joint meeting of the 19th annual Diabetic Neuropathy Study Group of the European Association for the Study of Diabetes (NEURODIAB) and the 8th International Symposium on Diabetic Neuropathy in Toronto, Canada, 13-18 October 2009, expert panels were convened to provide updates on cla...... on classification, definitions, diagnostic criteria, and treatments of diabetic peripheral neuropathies (DPNs), autonomic neuropathy, painful DPNs, and structural alterations in DPNs.......Preceding the joint meeting of the 19th annual Diabetic Neuropathy Study Group of the European Association for the Study of Diabetes (NEURODIAB) and the 8th International Symposium on Diabetic Neuropathy in Toronto, Canada, 13-18 October 2009, expert panels were convened to provide updates...

Mixed Portmanteau Test for Diagnostic Checking of Time Series Models

Directory of Open Access Journals (Sweden)

Sohail Chand

2014-01-01

Full Text Available Model criticism is an important stage of model building and thus goodness of fit tests provides a set of tools for diagnostic checking of the fitted model. Several tests are suggested in literature for diagnostic checking. These tests use autocorrelation or partial autocorrelation in the residuals to criticize the adequacy of fitted model. The main idea underlying these portmanteau tests is to identify if there is any dependence structure which is yet unexplained by the fitted model. In this paper, we suggest mixed portmanteau tests based on autocorrelation and partial autocorrelation functions of the residuals. We derived the asymptotic distribution of the mixture test and studied its size and power using Monte Carlo simulations.

Evaluation of the Effect of Diagnostic Molecular Testing on the Surgical Decision-Making Process for Patients With Thyroid Nodules.

Science.gov (United States)

Noureldine, Salem I; Najafian, Alireza; Aragon Han, Patricia; Olson, Matthew T; Genther, Dane J; Schneider, Eric B; Prescott, Jason D; Agrawal, Nishant; Mathur, Aarti; Zeiger, Martha A; Tufano, Ralph P

2016-07-01

Diagnostic molecular testing is used in the workup of thyroid nodules. While these tests appear to be promising in more definitively assigning a risk of malignancy, their effect on surgical decision making has yet to be demonstrated. To investigate the effect of diagnostic molecular profiling of thyroid nodules on the surgical decision-making process. A surgical management algorithm was developed and published after peer review that incorporated individual Bethesda System for Reporting Thyroid Cytopathology classifications with clinical, laboratory, and radiological results. This algorithm was created to formalize the decision-making process selected herein in managing patients with thyroid nodules. Between April 1, 2014, and March 31, 2015, a prospective study of patients who had undergone diagnostic molecular testing of a thyroid nodule before being seen for surgical consultation was performed. The recommended management undertaken by the surgeon was then prospectively compared with the corresponding one in the algorithm. Patients with thyroid nodules who did not undergo molecular testing and were seen for surgical consultation during the same period served as a control group. All pertinent treatment options were presented to each patient, and any deviation from the algorithm was recorded prospectively. To evaluate the appropriateness of any change (deviation) in management, the surgical histopathology diagnosis was correlated with the surgery performed. The study cohort comprised 140 patients who underwent molecular testing. Their mean (SD) age was 50.3 (14.6) years, and 75.0% (105 of 140) were female. Over a 1-year period, 20.3% (140 of 688) had undergone diagnostic molecular testing before surgical consultation, and 79.7% (548 of 688) had not undergone molecular testing. The surgical management deviated from the treatment algorithm in 12.9% (18 of 140) with molecular testing and in 10.2% (56 of 548) without molecular testing (P = .37). In the group with

Development of diagnostic test instruments to reveal level student conception in kinematic and dynamics

Science.gov (United States)

Handhika, J.; Cari, C.; Suparmi, A.; Sunarno, W.; Purwandari, P.

2018-03-01

The purpose of this research was to develop a diagnostic test instrument to reveal students' conceptions in kinematics and dynamics. The diagnostic test was developed based on the content indicator the concept of (1) displacement and distance, (2) instantaneous and average velocity, (3) zero and constant acceleration, (4) gravitational acceleration (5) Newton's first Law, (6) and Newton's third Law. The diagnostic test development model includes: Diagnostic test requirement analysis, formulating test-making objectives, developing tests, checking the validity of the content and the performance of reliability, and application of tests. The Content Validation Index (CVI) results in the category are highly relevant, with a value of 0.85. Three questions get negative Content Validation Ratio CVR) (-0.6), after revised distractors and clarify visual presentation; the CVR become 1 (highly relevant). This test was applied, obtained 16 valid test items, with Cronbach Alpha value of 0.80. It can conclude that diagnostic test can be used to reveal the level of students conception in kinematics and dynamics.

Rapid diagnostic tests for typhoid and paratyphoid (enteric) fever

Science.gov (United States)

Wijedoru, Lalith; Mallett, Sue; Parry, Christopher M

2017-01-01

Background Differentiating both typhoid (Salmonella Typhi) and paratyphoid (Salmonella Paratyphi A) infection from other causes of fever in endemic areas is a diagnostic challenge. Although commercial point-of-care rapid diagnostic tests (RDTs) for enteric fever are available as alternatives to the current reference standard test of blood or bone marrow culture, or to the widely used Widal Test, their diagnostic accuracy is unclear. If accurate, they could potentially replace blood culture as the World Health Organization (WHO)-recommended main diagnostic test for enteric fever. Objectives To assess the diagnostic accuracy of commercially available rapid diagnostic tests (RDTs) and prototypes for detecting Salmonella Typhi or Paratyphi A infection in symptomatic persons living in endemic areas. Search methods We searched the Cochrane Infectious Diseases Group Specialized Register, MEDLINE, Embase, Science Citation Index, IndMED, African Index Medicus, LILACS, ClinicalTrials.gov, and the World Health Organization (WHO) International Clinical Trials Registry Platform (ICTRP) up to 4 March 2016. We manually searched WHO reports, and papers from international conferences on Salmonella infections. We also contacted test manufacturers to identify studies. Selection criteria We included diagnostic accuracy studies of enteric fever RDTs in patients with fever or with symptoms suggestive of enteric fever living in endemic areas. We classified the reference standard used as either Grade 1 (result from a blood culture and a bone marrow culture) or Grade 2 (result from blood culture and blood polymerase chain reaction, or from blood culture alone). Data collection and analysis Two review authors independently extracted the test result data. We used a modified QUADAS-2 extraction form to assess methodological quality. We performed a meta-analysis when there were sufficient studies for the test and heterogeneity was reasonable. Main results Thirty-seven studies met the inclusion

21 CFR 601.31 - Definition.

Science.gov (United States)

2010-04-01

... 21 Food and Drugs 7 2010-04-01 2010-04-01 false Definition. 601.31 Section 601.31 Food and Drugs... Diagnostic Radiopharmaceuticals § 601.31 Definition. For purposes of this part,diagnostic radiopharmaceutical means: (a) An article that is intended for use in the diagnosis or monitoring of a disease or a...

21 CFR 315.2 - Definition.

Science.gov (United States)

2010-04-01

... 21 Food and Drugs 5 2010-04-01 2010-04-01 false Definition. 315.2 Section 315.2 Food and Drugs... DIAGNOSTIC RADIOPHARMACEUTICALS § 315.2 Definition. For purposes of this part, diagnostic radiopharmaceutical means: (a) An article that is intended for use in the diagnosis or monitoring of a disease or a...

Diagnostic value of serologic tests in celiac screening

Directory of Open Access Journals (Sweden)

Hosein Saneian

2012-01-01

Conclusions: According to our study results, there is no correlation between gastrointestinal symptoms such as vomiting diarrhea, anorexia, bulimia, and failure to thrive (FFT with celiac. TTG was the best screening test method to diagnose celiac disease and other tests such as AGA and EMA do not have high diagnostic value.

The diagnostic odds ratio: a single indicator of test performance

NARCIS (Netherlands)

Glas, Afina S.; Lijmer, Jeroen G.; Prins, Martin H.; Bonsel, Gouke J.; Bossuyt, Patrick M. M.

2003-01-01

Diagnostic testing can be used to discriminate subjects with a target disorder from subjects without it. Several indicators of diagnostic performance have been proposed, such as sensitivity and specificity. Using paired indicators can be a disadvantage in comparing the performance of competing

Diagnostic accuracy of temporomandibular disorder pain tests: a multicenter study

NARCIS (Netherlands)

Visscher, C.M.; Naeije, M.; de Laat, A.; Michelotti, A.; Nilner, M.; Craane, B.; Ekberg, E.; Farella, M.; Lobbezoo, F.

2009-01-01

AIMS: To estimate the diagnostic accuracy of the Research Diagnostic Criteria for Temporomandibular Disorders (RDC/TMD) clinical examination and of the dynamic/static tests for the recognition of TMD pain. Since the diagnosis of TMD pain is especially complicated in persistent orofacial pain

Optimal Sequential Diagnostic Strategy Generation Considering Test Placement Cost for Multimode Systems

Directory of Open Access Journals (Sweden)

Shigang Zhang

2015-10-01

Full Text Available Sequential fault diagnosis is an approach that realizes fault isolation by executing the optimal test step by step. The strategy used, i.e., the sequential diagnostic strategy, has great influence on diagnostic accuracy and cost. Optimal sequential diagnostic strategy generation is an important step in the process of diagnosis system construction, which has been studied extensively in the literature. However, previous algorithms either are designed for single mode systems or do not consider test placement cost. They are not suitable to solve the sequential diagnostic strategy generation problem considering test placement cost for multimode systems. Therefore, this problem is studied in this paper. A formulation is presented. Two algorithms are proposed, one of which is realized by system transformation and the other is newly designed. Extensive simulations are carried out to test the effectiveness of the algorithms. A real-world system is also presented. All the results show that both of them have the ability to solve the diagnostic strategy generation problem, and they have different characteristics.

Optimal Sequential Diagnostic Strategy Generation Considering Test Placement Cost for Multimode Systems

Science.gov (United States)

Zhang, Shigang; Song, Lijun; Zhang, Wei; Hu, Zheng; Yang, Yongmin

2015-01-01

Sequential fault diagnosis is an approach that realizes fault isolation by executing the optimal test step by step. The strategy used, i.e., the sequential diagnostic strategy, has great influence on diagnostic accuracy and cost. Optimal sequential diagnostic strategy generation is an important step in the process of diagnosis system construction, which has been studied extensively in the literature. However, previous algorithms either are designed for single mode systems or do not consider test placement cost. They are not suitable to solve the sequential diagnostic strategy generation problem considering test placement cost for multimode systems. Therefore, this problem is studied in this paper. A formulation is presented. Two algorithms are proposed, one of which is realized by system transformation and the other is newly designed. Extensive simulations are carried out to test the effectiveness of the algorithms. A real-world system is also presented. All the results show that both of them have the ability to solve the diagnostic strategy generation problem, and they have different characteristics. PMID:26457709

Background review for diagnostic test development for Zika virus infection.

Science.gov (United States)

Charrel, Rémi N; Leparc-Goffart, Isabelle; Pas, Suzan; de Lamballerie, Xavier; Koopmans, Marion; Reusken, Chantal

2016-08-01

To review the state of knowledge about diagnostic testing for Zika virus infection and identify areas of research needed to address the current gaps in knowledge. We made a non-systematic review of the published literature about Zika virus and supplemented this with information from commercial diagnostic test kits and personal communications with researchers in European preparedness networks. The review covered current knowledge about the geographical spread, pathogen characteristics, life cycle and infection kinetics of the virus. The available molecular and serological tests and biosafety issues are described and discussed in the context of the current outbreak strain. We identified the following areas of research to address current knowledge gaps: (i) an urgent assessment of the laboratory capacity and capability of countries to detect Zika virus; (ii) rapid and extensive field validation of the available molecular and serological tests in areas with and without Zika virus transmission, with a focus on pregnant women; (iii) monitoring the genomic diversity of circulating Zika virus strains; (iv) prospective studies into the virus infection kinetics, focusing on diagnostic sampling (specimen types, combinations and timings); and (v) developing external quality assessments for molecular and serological testing, including differential diagnosis for similar viruses and symptom clusters. The availability of reagents for diagnostic development (virus strains and antigens, quantified viral ribonucleic acid) needs to be facilitated. An international laboratory response is needed, including preparation of protocols for prospective studies to address the most pressing information needs.

Can Emergency Medicine Residents Predict Cost of Diagnostic Testing?

Directory of Open Access Journals (Sweden)

Tainter, Christopher R

2017-01-01

Full Text Available Diagnostic testing represents a significant portion of healthcare spending, and cost should be considered when ordering such tests. Needless and excessive spending may occur without an appreciation of the impact on the larger healthcare system. Knowledge regarding the cost of diagnostic testing among emergency medicine (EM residents has not previously been studied. A survey was administered to 20 EM residents from a single ACGME-accredited three-year EM residency program, asking for an estimation of patient charges for 20 commonly ordered laboratory tests and seven radiological exams. We compared responses between residency classes to evaluate whether there was a difference based on level of training. The survey completion rate was 100% (20/20 residents. We noted significant discrepancies between the median resident estimates and actual charge to patient for both laboratory and radiological exams. Nearly all responses were an underestimate of the actual cost. The group median underestimation for laboratory testing was $114, for radiographs $57, and for computed tomography exams was $1,058. There was improvement in accuracy with increasing level of training. This pilot study demonstrates that EM residents have a poor understanding of the charges burdening patients and health insurance providers. In order to make balanced decisions with regard to diagnostic testing, providers must appreciate these factors. Education regarding the cost of providing emergency care is a potential area for improvement of EM residency curricula, and warrants further attention and investigation.

Case definition for progressive multifocal leukoencephalopathy following treatment with monoclonal antibodies.

Science.gov (United States)

Mentzer, Dirk; Prestel, Jürgen; Adams, Ortwin; Gold, Ralf; Hartung, Hans-Peter; Hengel, Hartmut; Kieseier, Bernd C; Ludwig, Wolf-Dieter; Keller-Stanislawski, Brigitte

2012-09-01

Novel immunosuppressive/modulating therapies with monoclonal antibodies (MABs) have been associated with progressive multifocal leukoencephalopathy (PML), a potentially fatal disease of the brain caused by the JC virus. Taking the complex diagnostic testing and heterogeneous clinical presentation of PML into account, an agreed case definition for PML is a prerequisite for a thorough assessment of PML. A working group was established to develop a standardised case definition for PML which permits data comparability across clinical trials, postauthorisation safety studies and passive postmarketing surveillance. The case definition is designed to define levels of diagnostic certainty of reported PML cases following treatment with MABs. It was subsequently used to categorise retrospectively suspected PML cases from Germany reported to the Paul-Ehrlich-Institute as the responsible national competent authority. The algorithm of the case definition is based on clinical symptoms, PCR for JC virus DNA in cerebrospinal fluid, brain MRI, and brain biopsy/autopsy. The case definition was applied to 119 suspected cases of PML following treatment with MABs and is considered to be helpful for case ascertainment of suspected PML cases for various MABs covering a broad spectrum of indications. Even if the available information is not yet complete, the case definition provides a level of diagnostic certainty. The proposed case definition permits data comparability among different medicinal products and among active as well as passive surveillance settings. It may form a basis for meaningful risk analysis and communication for regulators and healthcare professionals.

Laboratory development and testing of spacecraft diagnostics

Science.gov (United States)

Amatucci, William; Tejero, Erik; Blackwell, Dave; Walker, Dave; Gatling, George; Enloe, Lon; Gillman, Eric

2017-10-01

The Naval Research Laboratory's Space Chamber experiment is a large-scale laboratory device dedicated to the creation of large-volume plasmas with parameters scaled to realistic space plasmas. Such devices make valuable contributions to the investigation of space plasma phenomena under controlled, reproducible conditions, allowing for the validation of theoretical models being applied to space data. However, in addition to investigations such as plasma wave and instability studies, such devices can also make valuable contributions to the development and testing of space plasma diagnostics. One example is the plasma impedance probe developed at NRL. Originally developed as a laboratory diagnostic, the sensor has now been flown on a sounding rocket, is included on a CubeSat experiment, and will be included on the DoD Space Test Program's STP-H6 experiment on the International Space Station. In this talk, we will describe how the laboratory simulation of space plasmas made this development path possible. Work sponsored by the US Naval Research Laboratory Base Program.

Selective Mutism: Definition, Issues, and Treatment.

Science.gov (United States)

Brigham, Frederick J.; Cole, Jane E.

This paper reviews definitions and issues in selective mutism in children and summarizes results of interventions conducted and published since 1982. Definitions and diagnostic criteria of the American Psychiatric Association's "Diagnostic and Statistical Manual of Mental Disorders (DSM-IV) (1994)" and the World Health Organization's…

30 CFR 250.523 - How long do I keep records of casing pressure and diagnostic tests?

Science.gov (United States)

2010-07-01

... and diagnostic tests? 250.523 Section 250.523 Mineral Resources MINERALS MANAGEMENT SERVICE... casing pressure and diagnostic tests? Records of casing pressure and diagnostic tests must be kept at the field office nearest the well for a minimum of 2 years. The last casing diagnostic test for each casing...

Aquifer test interpretation using derivative analysis and diagnostic plots

Science.gov (United States)

Hernández-Espriú, Antonio; Real-Rangel, Roberto; Cortés-Salazar, Iván; Castro-Herrera, Israel; Luna-Izazaga, Gabriela; Sánchez-León, Emilio

2017-04-01

Pumping tests remain a method of choice to deduce fundamental aquifer properties and to assess well condition. In the oil and gas (O&G) industry, well testing has been the core technique in examining reservoir behavior over the last 50 years. The pressure derivative by Bourdet, it is perhaps, the most significant single development in the history of well test analysis. Recently, the so-called diagnostics plots (e.g. drawdown and drawdown derivative in a log-log plot) have been successfully tested in aquifers. However, this procedure is still underutilized by groundwater professionals. This research illustrates the applicability range, advantages and drawbacks (e.g. smoothing procedures) of diagnostic plots using field examples from a wide spectrum of tests (short/long tests, constant/variable flow rates, drawdown/buildup stages, pumping well/observation well) in dissimilar geological conditions. We analyze new and pre-existent aquifer tests in Mexico, USA, Canada, Germany, France and Saudi Arabia. In constant flow rate tests, our results show that derivative analysis is an easy, robust and powerful tool to assess near-borehole damage effects, formation heterogeneity, boundaries, flow regimes, infinite-acting radial stages, i.e., valid Theisian framework, and fracture-driven flow. In step tests, the effectiveness relies on high-frequency drawdown measurements. Moreover, we adapt O&G analytical solutions to cater for the conditions in groundwater systems. In this context, further parameters can be computed analytically from the plots, such as skin factor, head losses, wellbore storage, distance to the boundary, channel-aquifer and/or fracture zone width, among others. Therefore, diagnostic plots should be considered a mandatory tool for pumping tests analysis among hydrogeologists. This project has been supported by DGAPA (UNAM) under the research project PAPIIT IN-112815.

Assessing Old and New Diagnostic Tests for Gastroesophageal Reflux Disease.

Science.gov (United States)

Vaezi, Michael F; Sifrim, Daniel

2018-01-01

A detailed critique of objective measurements of gastroesophageal reflux disease (GERD) would improve management of patients suspecting of having reflux, leading to rational selection of treatment and better outcomes. Many diagnostic tests for GERD have been developed over the past decades. We analyze their development, positive- and negative-predictive values, and ability to predict response to treatment. These features are important for development of medical, surgical, and endoscopic therapies for GERD. We discuss the value of available diagnostic tests and review their role in management of patients with persistent reflux symptoms despite adequate medical or surgical treatment. This is becoming a significant health economic problem, due to the widespread use of proton pump inhibitors. GERD is believed to cause nonesophageal symptoms, such as those provoked by ear, nose, throat, or respiratory disorders. We analyze the value of GERD diagnostic tests in evaluation of these troublesome, nonesophageal symptoms. Copyright © 2018 AGA Institute. Published by Elsevier Inc. All rights reserved.

DIAGNOSTIC CHARACTERISTICS OF THE COMPUTER TESTS FORMED BY METHOD OF RESTORED FRAGMENTS

OpenAIRE

Oleksandr O. Petkov

2013-01-01

Definition of validity and reliability of tests which are formed by a method of restored fragments is considered in the article. The structure of the controlled theoretical material of limit field of knowledge, language expressions that describe the subject of control, and reliability of test, is analyzed. The technique of definition of the most important components of reliability of the considered tests is given: reliability of quantitative determination of coefficient of assimilation and te...

Dry Eye Disease: Concordance Between the Diagnostic Tests in African Eyes.

Science.gov (United States)

Onwubiko, Stella N; Eze, Boniface I; Udeh, Nnenma N; Onwasigwe, Ernest N; Umeh, Rich E

2016-11-01

To assess the concordance between the diagnostic tests for dry eye disease (DED) in a Nigerian hospital population. The study was a hospital-based cross-sectional survey of adults (≥18 years) presenting at the eye clinic of the University of Nigeria Teaching Hospital (UNTH), Enugu; September-December, 2011. Participants' socio-demographic data were collected. Each subject was assessed for DED using the "Ocular Surface Disease Index" (OSDI) questionnaire, tear-film breakup time (TBUT), and Schirmer test. The intertest concordance was assessed using kappa statistic, correlation, and regression coefficients. The participants (n=402; men: 193) were aged 50.1±19.1 standard deviation years (range: 18-94 years). Dry eye disease was diagnosed in 203 by TBUT, 170 by Schirmer test, and 295 by OSDI; the concordance between the tests were OSDI versus TBUT (Kappa, κ=-0.194); OSDI versus Schirmer (κ=-0.276); and TBUT versus Schirmer (κ=0.082). Ocular Surface Disease Index was inversely correlated with Schirmer test (Spearman ρ=-0.231, P<0.001) and TBUT (ρ=-0.237, P<0.001). In the linear regression model, OSDI was poorly predicted by TBUT (β=-0.09; 95% confidence interval (CI): -0.26 to -0.03, P=0.14) and Schirmer test (β=-0.35, 95% CI: -0.53 to -0.18, P=0.18). At UNTH, there is poor agreement, and almost equal correlation, between the subjective and objective tests for DED. Therefore, the selection of diagnostic test for DED should be informed by cost-effectiveness and diagnostic resource availability, not diagnostic efficiency or utility.

Genetic test utilization and diagnostic yield in adult patients with neurological disorders.

Science.gov (United States)

Bardakjian, Tanya M; Helbig, Ingo; Quinn, Colin; Elman, Lauren B; McCluskey, Leo F; Scherer, Steven S; Gonzalez-Alegre, Pedro

2018-03-28

To determine the diagnostic yield of different genetic test modalities in adult patients with neurological disorders, we evaluated all adult patients seen for genetic diagnostic evaluation in the outpatient neurology practice at the University of Pennsylvania between January 2016 and April 2017 as part of the newly created Penn Neurogenetics Program. Subjects were identified through our electronic medical system as those evaluated by the Program's single clinical genetic counselor in that period. A total of 377 patients were evaluated by the Penn Neurogenetics Program in different settings and genetic testing recommended. Of those, 182 (48%) were seen in subspecialty clinic setting and 195 (52%) in a General Neurogenetics Clinic. Genetic testing was completed in over 80% of patients in whom it was recommended. The diagnostic yield was 32% across disease groups. Stratified by testing modality, the yield was highest with directed testing (50%) and array comparative genomic hybridization (45%), followed by gene panels and exome testing (25% each). In conclusion, genetic testing can be successfully requested in clinic in a large majority of adult patients. Age is not a limiting factor for a genetic diagnostic evaluation and the yield of clinical testing across phenotypes (almost 30%) is consistent with previous phenotype-focused or research-based studies. These results should inform the development of specific guidelines for clinical testing and serve as evidence to improve reimbursement by insurance payers.

Efficient Noninferiority Testing Procedures for Simultaneously Assessing Sensitivity and Specificity of Two Diagnostic Tests

Directory of Open Access Journals (Sweden)

Guogen Shan

2015-01-01

Full Text Available Sensitivity and specificity are often used to assess the performance of a diagnostic test with binary outcomes. Wald-type test statistics have been proposed for testing sensitivity and specificity individually. In the presence of a gold standard, simultaneous comparison between two diagnostic tests for noninferiority of sensitivity and specificity based on an asymptotic approach has been studied by Chen et al. (2003. However, the asymptotic approach may suffer from unsatisfactory type I error control as observed from many studies, especially in small to medium sample settings. In this paper, we compare three unconditional approaches for simultaneously testing sensitivity and specificity. They are approaches based on estimation, maximization, and a combination of estimation and maximization. Although the estimation approach does not guarantee type I error, it has satisfactory performance with regard to type I error control. The other two unconditional approaches are exact. The approach based on estimation and maximization is generally more powerful than the approach based on maximization.

Compounding diagnostic delays: a qualitative study of point-of-care testing in South Africa.

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Engel, Nora; Davids, Malika; Blankvoort, Nadine; Pai, Nitika Pant; Dheda, Keertan; Pai, Madhukar

2015-04-01

Successful point-of-care (POC) testing (completion of test-and-treat cycle in one patient encounter) has immense potential to reduce diagnostic and treatment delays, and improve patient and public health outcomes. We explored what tests are done and how in public/private, rural/urban hospitals and clinics in South Africa and whether they can ensure successful POC testing. This qualitative research study examined POC testing across major diseases in Cape Town, Durban and Eastern Cape. We conducted 101 semi-structured interviews and seven focus group discussions with doctors, nurses, community health workers, patients, laboratory technicians, policymakers, hospital managers and diagnostic manufacturers. In South Africa, diagnostics are characterised by a centralised system. Most tests conducted on the spot can be made to work successfully as POC tests. The majority of public/private clinics and smaller hospitals send samples via couriers to centralised laboratories and retrieve results the same way, via internet, fax or phone. The main challenge to POC testing lies in transporting samples and results, while delays risk patient loss from diagnostic/treatment pathways. Strategies to deal with associated delays create new problems, such as artificially prolonged turnaround times, strains on human resources and quality of testing, compounding additional diagnostic and treatment delays. For POC testing to succeed, particular characteristics of diagnostic ecosystems and adaptations of professional practices to overcome associated challenges must be taken into account. © 2014 John Wiley & Sons Ltd.

A comparison of rapid diagnostic testing (by plasmodium lactate ...

African Journals Online (AJOL)

Background: The World Health Organization (WHO) considers early and rapid diagnosis as one of the strategies to control malaria. This study compared the performance of Quantitative Buffy Coat (QBC) test and the Plasmodium lactate dehydrogenase (pLDH) rapid diagnostic test (RDT) with microscopy as the gold ...

Receiver operating characteristic (ROC) curves and the definition of threshold levels to diagnose coronary artery disease on electrocardiographic stress testing. Part I: The use of ROC curves in diagnostic medicine and electrocardiographic markers of ischaemia.

Science.gov (United States)

Barnabei, Luca; Marazìa, Stefania; De Caterina, Raffaele

2007-11-01

A common problem in diagnostic medicine, when performing a diagnostic test, is to obtain an accurate discrimination between 'normal' cases and cases with disease, owing to the overlapping distributions of these populations. In clinical practice, it is exceedingly rare that a chosen cut point will achieve perfect discrimination between normal cases and those with disease, and one has to select the best compromise between sensitivity and specificity by comparing the diagnostic performance of different tests or diagnostic criteria available. Receiver operating characteristic (or receiver operator characteristic, ROC) curves allow systematic and intuitively appealing descriptions of the diagnostic performance of a test and a comparison of the performance of different tests or diagnostic criteria. This review will analyse the basic principles underlying ROC curves and their specific application to the choice of optimal parameters on exercise electrocardiographic (ECG) stress testing. Part I will focus on theoretical description and analysis along with reviewing the common problems related to the diagnosis of myocardial ischaemia by means of exercise ECG stress testing. Part II will be devoted to applying ROC curves to available diagnostic criteria through the analysis of ECG stress test parameters.

The diagnostic value of component-resolved diagnostics in peanut allergy in children attending a Regional Paediatric Allergology Clinic.

Science.gov (United States)

van Veen, Leonieke N; Heron, Michiel; Batstra, Manou; van Haard, Paul M M; de Groot, Hans

2016-06-02

To date, diagnosing food allergies in children still presents a diagnostic dilemma, leading to uncertainty concerning the definite diagnosis of peanut allergy, as well as to the need for strict diets and the potential need for adrenalin auto-injectors. This uncertainty in particular is thought to contribute to a lower quality of life. In the diagnostic process double-blind food challenges are considered the gold standard, but they are time-consuming as well as potentially hazardous. Other diagnostic tests have been extensively studied and among these component-resolved diagnostics appeared to present a promising alternative: Ara h2, a peanut storage protein in previous studies showed to have a significant predictive value. Sixty-two out of 72 children, with suspected peanut allergy were analyzed using serum specific IgE and/or skin prick tests and specific IgE to several components of peanut (Ara h 1, 2, 3, 6, 8, 9). Subsequently, double-blind food challenges were performed. The correlation between the various diagnostic tests and the overall outcome of the double-blind food challenges were studied, in particular the severity of the reaction and the eliciting dose. The double-blind provocation with peanut was positive in 33 children (53 %). There was no relationship between the eliciting dose and the severity of the reaction. A statistically significant relationship was found between the skin prick test, specific IgE directed to peanut, Ara h 1, Ara h 2 or Ara h 6, and the outcome of the food challenge test, in terms of positive or negative (P food challenge. This study shows that component-resolved diagnostics is not superior to specific IgE to peanut extract or to skin prick testing. At present, it cannot replace double-blind placebo-controlled food challenges for determination of the eliciting dose or the severity of the peanut allergy in our patient group.

Technology diffusion and diagnostic testing for prostate cancer

Science.gov (United States)

Schroeck, Florian R.; Kaufman, Samuel R.; Jacobs, Bruce L.; Skolarus, Ted A.; Miller, David C.; Weizer, Alon Z.; Montgomery, Jeffrey S.; Wei, John T.; Shahinian, Vahakn B.; Hollenbeck, Brent K.

2013-01-01

Purpose While the dissemination of robotic prostatectomy and intensity-modulated radiotherapy (IMRT) may fuel increased use of prostatectomy and radiotherapy, these new technologies may also have spillover effects related to diagnostic testing for prostate cancer. Therefore, we examined the association of regional technology penetration with receipt of prostate specific antigen (PSA) testing and prostate biopsy. Methods In this retrospective cohort study, we included 117,857 men age 66 and older from the 5% sample of Medicare beneficiaries living in the Surveillance Epidemiology and End Results (SEER) areas from 2003 – 2007. Regional technology penetration was measured as the number of providers performing robotic prostatectomy or IMRT per population in a healthcare market (i.e., hospital referral region). We assessed the association of technology penetration with rates of PSA testing and prostate biopsy with generalized estimating equations. Results High technology penetration was associated with increased rates of PSA testing (442 versus 425 per 1,000 person-years, pimpact of technology penetration on PSA testing and prostate biopsy was much smaller than the effect of age, race, and comorbidity (e.g., PSA testing rate per 1,000 person-years: 485 versus 373 for men with only one versus 3+ co-morbid conditions, ppenetration was associated with slightly higher rates of PSA testing and no change in prostate biopsy rates. Collectively, our findings temper concerns that adoption of new technology accelerates diagnostic testing for prostate cancer. PMID:23669564

Evaluation of Diagnostic Tests Using Information Theory for Multi-Class Diagnostic Problems and its Application for the Detection of Occlusal Caries Lesions

Directory of Open Access Journals (Sweden)

Umut Arslan

2014-09-01

Full Text Available Background: Several methods are available to evaluate the performance of the tests when the purpose of the diagnostic test is to discriminate between two possible disease states. However multi-class diagnostic problems frequently appear in many areas of medical science. Hence, there is a need for methods which will enable us to characterize the accuracy of diagnostic tests when there are more than two possible disease states. Aims: To show that two information theory measures, information content (IC and proportional reduction in diagnostic uncertainty (PRDU, can be used for the evaluation of the performance of diagnostic tests for multi-class diagnostic problems that may appear in different areas of medical science. Study Design: Diagnostic accuracy study. Methods: Sixty freshly extracted permanent human molar and premolar teeth suspected to have occlusal caries lesions were selected for the study and were assessed by two experienced examiners. Each examiner performed two evaluations. Histological examination was used as the gold standard. The scores of the histological examination were defined as sound (n=11, enamel caries (n=22 and dentin caries (n=27. Diagnostic performance of i visual inspection, ii radiography, iii laser fluorescence (LF and iv micro-computed tomography (M-CT caries detection methods was evaluated by calculating IC and PRDU. Results: Micro-computed tomography examination was the best method among the diagnostic techniques for the diagnosis of occlusal caries in terms of both IC and PRDU. M-CT examination supplied the maximum diagnostic information about the diagnosis of occlusal caries in the first (IC: 1.056; p<0.05, (PRDU: 70.5% and second evaluation (IC: 1.105; p<0.05, (PRDU: 73.8% for the first examiner. M-CT examination was the best method among the diagnostic techniques for the second examiner in both the first (IC:1.105; p<0.05, (PRDU:73.8% and second evaluation (IC:1.061; p<0.05, (PRDU:70.8%. IC and PRDU were

Diagnostic depressive symptoms of the mixed bipolar episode.

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Cassidy, F; Ahearn, E; Murry, E; Forest, K; Carroll, B J

2000-03-01

There is not yet consensus on the best diagnostic definition of mixed bipolar episodes. Many have suggested the DSM-III-R/-IV definition is too rigid. We propose alternative criteria using data from a large patient cohort. We evaluated 237 manic in-patients using DSM-III-R criteria and the Scale for Manic States (SMS). A bimodally distributed factor of dysphoric mood has been reported from the SMS data. We used both the factor and the DSM-III-R classifications to identify candidate depressive symptoms and then developed three candidate depressive symptom sets. Using ROC analysis we determined the optimal threshold number of symptoms in each set and compared the three ROC solutions. The optimal solution was tested against the DSM-III-R classification for crossvalidation. The optimal ROC solution was a set, derived from both the DSM-III-R and the SMS, and the optimal threshold for diagnosis was two or more symptoms. Applying this set iteratively to the DSM-III-R classification produced the identical ROC solution. The prevalence of mixed episodes in the cohort was 13.9% by DSM-III-R, 20.2% by the dysphoria factor and 27.4% by the new ROC solution. A diagnostic set of six dysphoric symptoms (depressed mood, anhedonia, guilt, suicide, fatigue and anxiety), with a threshold of two symptoms, is proposed for a mixed episode. This new definition has a foundation in clinical data, in the proved diagnostic performance of the qualifying symptoms, and in ROC validation against two previous definitions that each have face validity.

Cost Implications of Value-Based Pricing for Companion Diagnostic Tests in Precision Medicine.

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Zaric, Gregory S

2016-07-01

Many interpretations of personalized medicine, also referred to as precision medicine, include discussions of companion diagnostic tests that allow drugs to be targeted to those individuals who are most likely to benefit or that allow treatment to be designed in a way such that individuals who are unlikely to benefit do not receive treatment. Many authors have commented on the clinical and competitive implications of companion diagnostics, but there has been relatively little formal analysis of the cost implications of companion diagnostics, although cost reduction is often cited as a significant benefit of precision medicine. We investigate the potential impact on costs of precision medicine implemented through the use of companion diagnostics. We develop a framework in which the costs of companion diagnostic tests are determined by considerations of profit maximization and cost effectiveness. We analyze four scenarios that are defined by the incremental cost-effectiveness ratio of the new drug in the absence of a companion diagnostic test. We find that, in most scenarios, precision medicine strategies based on companion diagnostics should be expected to lead to increases in costs in the short term and that costs would fall only in a limited number of situations.

Charge correlations as definitive tests of QCD

International Nuclear Information System (INIS)

Maxwell, C.J.

1981-07-01

Certain weighted charge correlations are defined and it is shown how they can be used to measure properties of the gluon jet in the e + e - 3-jet final state. Properties are suggested which are indicative of the form of the QCD matrix element, the running coupling constant and value of Λ, and hence constitute definitive tests of QCD. The recent near tenfold increase in luminosity at PETRA should make such experimental tests possible in the near future. (author)

Developing and Standardization of a Diagnostic Reading Test

Directory of Open Access Journals (Sweden)

Tahereh Sima-Shirazi

2004-06-01

Full Text Available Objective: This paper is a report on the development, structure and content of a diagnostic dyslexia reading test. The target population of this test is persian children who have problems in learning reading and may be considered as dyslexic. This diagnostic test is the first reading test developed for the native speakers of persian. Materials & Methods: The theoretical framework of the test is based on two well- established reading tests for the English speaking children, namely Durrell Analysis of Reading and Neale Analysis of Reading Ability. The linguistic content of the subtests is selected from the vocabulary and texts of the textbook used in the primary schools. Both the vocabulary and the sentences of the parrallel passeges were controlled for frequency, phonemic/graphemic regularity, syllable structure, morphology, syntax and semantics. They were also controlled for value judgement by two linguistics and three first grader teachers.The first version of the test is normed on 605 boy and girl first graders from different educational sectors and schools selected randomly.The method used in this research is cross- sectional, descriptive- analytic and the data analysis is based on pearson, and mann-whitney u. Results: Reliability of the test is calculated based on parrallel forms (~ 90% and validity is based on content validity.This test has a supplementary section including spelling, graphem/ phoneme correspondness, nonword reading, irregular word reading, and copy subtests. Conclusion: Considering highreliability and precise validation of the test it can be used to diagnose the dyslexia and related linguistic impairments.

Systematic reviews of diagnostic tests in endocrinology: an audit of methods, reporting, and performance.

Science.gov (United States)

Spencer-Bonilla, Gabriela; Singh Ospina, Naykky; Rodriguez-Gutierrez, Rene; Brito, Juan P; Iñiguez-Ariza, Nicole; Tamhane, Shrikant; Erwin, Patricia J; Murad, M Hassan; Montori, Victor M

2017-07-01

Systematic reviews provide clinicians and policymakers estimates of diagnostic test accuracy and their usefulness in clinical practice. We identified all available systematic reviews of diagnosis in endocrinology, summarized the diagnostic accuracy of the tests included, and assessed the credibility and clinical usefulness of the methods and reporting. We searched Ovid MEDLINE, EMBASE, and Cochrane CENTRAL from inception to December 2015 for systematic reviews and meta-analyses reporting accuracy measures of diagnostic tests in endocrinology. Experienced reviewers independently screened for eligible studies and collected data. We summarized the results, methods, and reporting of the reviews. We performed subgroup analyses to categorize diagnostic tests as most useful based on their accuracy. We identified 84 systematic reviews; half of the tests included were classified as helpful when positive, one-fourth as helpful when negative. Most authors adequately reported how studies were identified and selected and how their trustworthiness (risk of bias) was judged. Only one in three reviews, however, reported an overall judgment about trustworthiness and one in five reported using adequate meta-analytic methods. One in four reported contacting authors for further information and about half included only patients with diagnostic uncertainty. Up to half of the diagnostic endocrine tests in which the likelihood ratio was calculated or provided are likely to be helpful in practice when positive as are one-quarter when negative. Most diagnostic systematic reviews in endocrine lack methodological rigor, protection against bias, and offer limited credibility. Substantial efforts, therefore, seem necessary to improve the quality of diagnostic systematic reviews in endocrinology.

A general diagnostic model applied to language testing data.

Science.gov (United States)

von Davier, Matthias

2008-11-01

Probabilistic models with one or more latent variables are designed to report on a corresponding number of skills or cognitive attributes. Multidimensional skill profiles offer additional information beyond what a single test score can provide, if the reported skills can be identified and distinguished reliably. Many recent approaches to skill profile models are limited to dichotomous data and have made use of computationally intensive estimation methods such as Markov chain Monte Carlo, since standard maximum likelihood (ML) estimation techniques were deemed infeasible. This paper presents a general diagnostic model (GDM) that can be estimated with standard ML techniques and applies to polytomous response variables as well as to skills with two or more proficiency levels. The paper uses one member of a larger class of diagnostic models, a compensatory diagnostic model for dichotomous and partial credit data. Many well-known models, such as univariate and multivariate versions of the Rasch model and the two-parameter logistic item response theory model, the generalized partial credit model, as well as a variety of skill profile models, are special cases of this GDM. In addition to an introduction to this model, the paper presents a parameter recovery study using simulated data and an application to real data from the field test for TOEFL Internet-based testing.

Common pitfalls in statistical analysis: Understanding the properties of diagnostic tests - Part 1.

Science.gov (United States)

Ranganathan, Priya; Aggarwal, Rakesh

2018-01-01

In this article in our series on common pitfalls in statistical analysis, we look at some of the attributes of diagnostic tests (i.e., tests which are used to determine whether an individual does or does not have disease). The next article in this series will focus on further issues related to diagnostic tests.

Hantavirus pulmonary syndrome clinical findings: evaluating a surveillance case definition.

Science.gov (United States)

Knust, Barbara; Macneil, Adam; Rollin, Pierre E

2012-05-01

Clinical cases of hantavirus pulmonary syndrome (HPS) can be challenging to differentiate from other acute respiratory diseases, which can lead to delays in diagnosis, treatment, and disease reporting. Rapid onset of severe disease occurs, at times before diagnostic test results are available. This study's objective was to examine the clinical characteristics of patients that would indicate HPS to aid in detection and reporting. Test results of blood samples from U.S. patients suspected of having HPS submitted to the Centers for Disease Control and Prevention from 1998-2010 were reviewed. Patient information collected by case report forms was compared between HPS-confirmed and test-negative patients. Diagnostic sensitivity, specificity, predictive values, and likelihood ratios were calculated for individual clinical findings and combinations of variables. Of 567 patients included, 36% were HPS-confirmed. Thrombocytopenia, chest x-rays with suggestive signs, and receiving supplemental oxygenation were highly sensitive (>95%), while elevated hematocrit was highly specific (83%) in detecting HPS. Combinations that maximized sensitivity required the presence of thrombocytopenia. Using a national sample of suspect patients, we found that thrombocytopenia was a highly sensitive indicator of HPS and should be included in surveillance definitions for suspected HPS. Using a sensitive suspect case definition to identify potential HPS patients that are confirmed by highly specific diagnostic testing will ensure accurate reporting of this disease.

Diagnostic development and support of MHD (magnetohydrodynamics) test facilities

Energy Technology Data Exchange (ETDEWEB)

1989-07-01

Mississippi State University (MSU) is developing diagnostic instruments for Magnetohydrodynamics (MHD) power train data acquisition and for support of MHD component development test facilities. Microprocessor-controlled optical instruments, initially developed for HRSR support, are being refined, and new systems to measure temperatures and gas-seed-slag stream characteristics are being developed. To further data acquisition and analysis capabilities, the diagnostic systems are being interfaced with MHD Energy Center computers. Technical support for the diagnostic needs of the national MHD research effort is being provided. MSU personnel will also cooperate with government agencies and private industries to improve the transformation of research and development results into processes, products and services applicable to their needs.

The glucose breath test: a diagnostic test for small bowel stricture(s) in Crohn's disease.

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Mishkin, Daniel; Boston, Francis M; Blank, David; Yalovsky, Morty; Mishkin, Seymour

2002-03-01

The aim of this study was to determine whether an indirect noninvasive indicator of proximal bacterial overgrowth, the glucose breath test, was of diagnostic value in inflammatory bowel disease. Twenty four of 71 Crohn's disease patients tested had a positive glucose breath test. No statistical conclusions could be drawn between the Crohn's disease activity index and glucose breath test status. Of patients with radiologic evidence of small bowel stricture(s), 96.0% had a positive glucose breath test, while only one of 46 negative glucose breath test patients had a stricture. The positive and negative predictive values for a positive glucose breath test as an indicator of stricture formation were 96.0% and 97.8%, respectively. This correlation was not altered in Crohn's disease patients with fistulae or status postresection of the terminal ileum. The data in ulcerative colitis were nondiagnostic. In conclusion, the glucose breath test appears to be an accurate noninvasive inexpensive diagnostic test for small bowel stricture(s) and secondary bacterial overgrowth in Crohn's disease.

30 CFR 250.520 - When do I have to perform a casing diagnostic test?

Science.gov (United States)

2010-07-01

... 30 Mineral Resources 2 2010-07-01 2010-07-01 false When do I have to perform a casing diagnostic... Operations Casing Pressure Management § 250.520 When do I have to perform a casing diagnostic test? (a) You must perform a casing diagnostic test within 30 days after first observing or imposing casing pressure...

[Pathogenic Mechanism and Diagnostic Testing for Drug Allergies].

Science.gov (United States)

Uno, Katsuji

2018-01-01

　Three stages of the pathogenic mechanism of drug allergies can be considered: antigen formation, immune reaction and inflammation/disorder reaction. Drugs are thought to form 4 types of antigens: drug only, polymers, drug-carrier conjugates, and metabolite-carrier complexes. Antigens are recognized by B cell receptors and T cell receptors. Helper T cells (Th) are differentiated into four subsets, namely, Th1, Th2, Th17 and regulatory T cells (Treg). Th1 produces interleukin (IL)-2 and interferon (IFN)-γ, and activates macrophages and cytotoxic T cells (Tc). Macrophages induce type IV allergies, and Tc lead to serious type IV allergies. On the other hand, Th2 produces IL-4, IL-5, and IL-6, etc., and activates B cells. B cells produce IgE antibodies, and the IgE antibody affects mast cells and induces type I allergies. Activated eosinophil leads to the chronic state of type I allergy. Diagnostic testing for allergenic drugs is necessary for patients with drug allergies. Because in vivo diagnostic tests for allergenic drugs are associated with a risk and burden to the patient, in vitro allergy tests are recommended to identify allergenic drugs. In allergy tests performed in vitro, cytological tests are more effective than serological tests, and the leukocyte migration test (LMT) presently has the highest efficacy. An LMT-chamber is better than LMT-agarose in terms of usability and sensitivity, and it can detect about 80% of allergenic drugs.

Role of molecular testing in the multidisciplinary diagnostic approach of ichthyosis.

Science.gov (United States)

Diociaiuti, Andrea; El Hachem, May; Pisaneschi, Elisa; Giancristoforo, Simona; Genovese, Silvia; Sirleto, Pietro; Boldrini, Renata; Angioni, Adriano

2016-01-13

The term ichthyosis describes a generalized disorder of cornification characterized by scaling and/or hyperkeratosis of different skin regions. Mutations in a broad group of genes related to keratinocyte differentiation and epidermal barrier function have been demonstrated to play a causative role in disease development. Ichthyosis may be classified in syndromic or non-syndromic forms based on the occurrence or absence of extracutaneous signs. In this setting, the diagnosis of ichthyosis is an integrated multistep process requiring a multidisciplinary approach in order to formulate the appropriate diagnostic hypothesis and to address the genetic testing. Due to the complex features of the different ichthyoses and the high number of genes involved we have investigated a group of 64 patients, affected by syndromic and non-syndromic diseases, using Next Generation Sequencing as a new tool for the molecular diagnosis. Using this innovative molecular approach we were able to find pathogenic mutations in 53 out of 64 patients resulting in 82.8 % total detection rate. An interesting result from the analysis of the data is the high rate of novel sequence variations found compared to known mutations and the relevant rate of homozygous mutations. The possibility to analyze a large number of genes associated with various diseases allows to study cases with phenotypes not well-determined, giving the opportunity to make new genotype-phenotype correlation. In some cases there were discrepancies between clinical features and histology or electron microscopy and only molecular analysis allowed to definitively resolve the diagnostic dilemma. The genetic diagnosis of ichthyosis leads to a more accurate and effective genetic counseling, allowing correct evaluation of the risk of recurrence, particularly in families with consanguineous background.

Collaborative testing for key-term definitions under representative conditions: Efficiency costs and no learning benefits.

Science.gov (United States)

Wissman, Kathryn T; Rawson, Katherine A

2018-01-01

Students are expected to learn key-term definitions across many different grade levels and academic disciplines. Thus, investigating ways to promote understanding of key-term definitions is of critical importance for applied purposes. A recent survey showed that learners report engaging in collaborative practice testing when learning key-term definitions, with outcomes also shedding light on the way in which learners report engaging in collaborative testing in real-world contexts (Wissman & Rawson, 2016, Memory, 24, 223-239). However, no research has directly explored the effectiveness of engaging in collaborative testing under representative conditions. Accordingly, the current research evaluates the costs (with respect to efficiency) and the benefits (with respect to learning) of collaborative testing for key-term definitions under representative conditions. In three experiments (ns = 94, 74, 95), learners individually studied key-term definitions and then completed retrieval practice, which occurred either individually or collaboratively (in dyads). Two days later, all learners completed a final individual test. Results from Experiments 1-2 showed a cost (with respect to efficiency) and no benefit (with respect to learning) of engaging in collaborative testing for key-term definitions. Experiment 3 evaluated a theoretical explanation for why collaborative benefits do not emerge under representative conditions. Collectively, outcomes indicate that collaborative testing versus individual testing is less effective and less efficient when learning key-term definitions under representative conditions.

Get the Diagnosis: an evidence-based medicine collaborative Wiki for diagnostic test accuracy.

Science.gov (United States)

Hammer, Mark M; Kohlberg, Gavriel D

2017-04-01

Despite widespread calls for its use, there are challenges to the implementation of evidence-based medicine (EBM) in clinical practice. In response to the challenges of finding timely, pertinent information on diagnostic test accuracy, we developed an online, crowd-sourced Wiki on diagnostic test accuracy called Get the Diagnosis (GTD, http://www.getthediagnosis.org). Since its launch in November 2008 till October 2015, GTD has accumulated information on 300 diagnoses, with 1617 total diagnostic entries. There are a total of 1097 unique diagnostic tests with a mean of 5.4 tests (range 0-38) per diagnosis. 73% of entries (1182 of 1617) have an associated sensitivity and specificity and 89% of entries (1432 of 1617) have associated peer-reviewed literature citations. Altogether, GTD contains 474 unique literature citations. For a sample of three diagnoses, the search precision (percentage of relevant results in the first 30 entries) in GTD was 100% as compared with a range of 13.3%-63.3% for PubMed and between 6.7% and 76.7% for Google Scholar. GTD offers a fast, precise and efficient way to look up diagnostic test accuracy. On three selected examples, GTD had a greater precision rate compared with PubMed and Google Scholar in identifying diagnostic test information. GTD is a free resource that complements other currently available resources. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/.

What is the role of clinical tests and ultrasound in acetabular labral tear diagnostics?

DEFF Research Database (Denmark)

Troelsen, Anders; Mechlenburg, Inger; Gelineck, John

2009-01-01

BACKGROUND AND PURPOSE: An acetabular labral tear is a diagnostic challenge. Various clinical tests have been described, but little is known about their diagnostic sensitivity and specificity. We investigated the diagnostic validity of clinical tests and ultrasound as compared with MR arthrography...... no or only slight signs of osteoarthritis (Tönnis grade 0-1). RESULTS: MR arthrography identified labral tears in 17 of the 18 hips. Ultrasound had a sensitivity of 94%, a positive predictive value of 94%, and was false negative in only 1 case compared to MR arthrography. The impingement test had the best...... diagnostic ability of the clinical tests, with a sensitivity of 59% and a specificity of 100%. The positive predictive value was 100% while the negative predictive value was 13%. INTERPRETATION: The impingement test is helpful in identifying acetabular labral tears. If this test is negative and if a labral...

Diagnostic accuracy research in glaucoma is still incompletely reported: An application of Standards for Reporting of Diagnostic Accuracy Studies (STARD 2015.

Directory of Open Access Journals (Sweden)

Manuele Michelessi

Full Text Available Research has shown a modest adherence of diagnostic test accuracy (DTA studies in glaucoma to the Standards for Reporting of Diagnostic Accuracy Studies (STARD. We have applied the updated 30-item STARD 2015 checklist to a set of studies included in a Cochrane DTA systematic review of imaging tools for diagnosing manifest glaucoma.Three pairs of reviewers, including one senior reviewer who assessed all studies, independently checked the adherence of each study to STARD 2015. Adherence was analyzed on an individual-item basis. Logistic regression was used to evaluate the effect of publication year and impact factor on adherence.We included 106 DTA studies, published between 2003-2014 in journals with a median impact factor of 2.6. Overall adherence was 54.1% for 3,286 individual rating across 31 items, with a mean of 16.8 (SD: 3.1; range 8-23 items per study. Large variability in adherence to reporting standards was detected across individual STARD 2015 items, ranging from 0 to 100%. Nine items (1: identification as diagnostic accuracy study in title/abstract; 6: eligibility criteria; 10: index test (a and reference standard (b definition; 12: cut-off definitions for index test (a and reference standard (b; 14: estimation of diagnostic accuracy measures; 21a: severity spectrum of diseased; 23: cross-tabulation of the index and reference standard results were adequately reported in more than 90% of the studies. Conversely, 10 items (3: scientific and clinical background of the index test; 11: rationale for the reference standard; 13b: blinding of index test results; 17: analyses of variability; 18; sample size calculation; 19: study flow diagram; 20: baseline characteristics of participants; 28: registration number and registry; 29: availability of study protocol; 30: sources of funding were adequately reported in less than 30% of the studies. Only four items showed a statistically significant improvement over time: missing data (16, baseline

Technology diffusion and diagnostic testing for prostate cancer.

Science.gov (United States)

Schroeck, Florian R; Kaufman, Samuel R; Jacobs, Bruce L; Skolarus, Ted A; Miller, David C; Weizer, Alon Z; Montgomery, Jeffrey S; Wei, John T; Shahinian, Vahakn B; Hollenbeck, Brent K

2013-11-01

While the dissemination of robotic prostatectomy and intensity modulated radiotherapy may fuel the increased use of prostatectomy and radiotherapy, these new technologies may also have spillover effects related to diagnostic testing for prostate cancer. Therefore, we examined the association of regional technology penetration with the receipt of prostate specific antigen testing and prostate biopsy. In this retrospective cohort study we included 117,857 men 66 years old or older from the 5% sample of Medicare beneficiaries living in Surveillance, Epidemiology and End Results (SEER) areas from 2003 to 2007. Regional technology penetration was measured as the number of providers performing robotic prostatectomy or intensity modulated radiotherapy per population in a health care market, ie hospital referral region. We assessed the association of technology penetration with the prostate specific antigen testing rate and prostate biopsy using generalized estimating equations. High technology penetration was associated with an increased rate of prostate specific antigen testing (442 vs 425/1,000 person-years, pimpact of technology penetration on prostate specific antigen testing and prostate biopsy was much less than the effect of age, race and comorbidity, eg the prostate specific antigen testing rate per 1,000 person-years was 485 vs 373 for men with only 1 vs 3+ comorbid conditions (ppenetration is associated with a slightly higher rate of prostate specific antigen testing and no change in the prostate biopsy rate. Collectively, our findings temper concerns that adopting new technology accelerates diagnostic testing for prostate cancer. Copyright © 2013 American Urological Association Education and Research, Inc. Published by Elsevier Inc. All rights reserved.

Requirements for appropriate evaluation of diagnostic tests in suspected pulmonary embolism

NARCIS (Netherlands)

Sanson, B. J.; Meinders, A. J.; Kraaijenhagen, R. A.; van Beek, E. J.; Büller, H. R.

1999-01-01

In contrast to the development of new drugs, strict guidelines for the development of new diagnostic methods do not exist. A diagnostic test can be made available without proper evaluation of its clinical utility, which can lead to its premature introduction and inappropriate use. In this review

Beam Diagnostics for the BNL Energy Recovery Linac Test Facility

International Nuclear Information System (INIS)

Cameron, Peter; Ben-Zvi, Ilan; Blaskiewicz, Michael; Brennan, Michael; Connolly, Roger; Dawson, William; Degen, Chris; DellaPenna, Al; Gassner, David; Kesselman, Martin; Kewish, Jorg; Litvinenko, Vladimir; Mead, Joseph; Oerter, Brian; Russo, Tom; Vetter, Kurt; Yakimenko, Vitaly

2004-01-01

An Energy Recovery Linac (ERL) test facility is presently under construction at BNL. The goals of this test facility are first to demonstrate stable intense CW electron beam with parameters typical for the RHIC e-cooling project (and potentially for eRHIC), second to test novel elements of the ERL (high current CW photo-cathode, superconducting RF cavity with HOM dampers, and feedback systems), and finally to test lattice dependence of stability criteria. Planned diagnostics include position monitors, loss monitors, transverse profile monitors (both optical and wires), scrapers/halo monitors, a high resolution differential current monitor, phase monitors, an energy spread monitor, and a fast transverse monitor (for beam break-up studies and the energy feedback system). We discuss diagnostics challenges that are unique to this project, and present preliminary system specifications. In addition, we include a brief discussion of the timing system

Bovine paratuberculosis: a review of the advantages and disadvantages of different diagnostic tests.

Science.gov (United States)

Gilardoni, Liliana R; Paolicchi, Fernando A; Mundo, Silvia L

2012-01-01

Paratuberculosis (PTB), or Johne's disease, is a chronic infectious granulomatous enteritis of ruminants, caused by Mycobacterium avium subspecies paratuberculosis (Map). It is characterized by diarrhea and progressive cachexia, which may cause the death of the animal. Calves are the most susceptible to infection. Infected animals excrete Map mainly by the feces. PTB is endemic worldwide, with high prevalence levels, strong economic impact and public health relevance because of its possible association with Crohn's disease. Although the current reference diagnostic test is identification of Map in the bacterial culture, there are different diagnostic tests to identify infected individuals and/or herds. The sensitivity and specificity of these tests vary according to the stage of the disease in the animals to be evaluated. The correct choice and application of each of these diagnostic tests will ensure their success and may allow to establish a control program. The aim of this work is to review and discuss the different diagnostic tests used in the detection of Map-infected animals, focusing on their advantages and disadvantages.

Irregular analytical errors in diagnostic testing - a novel concept.

Science.gov (United States)

Vogeser, Michael; Seger, Christoph

2018-02-23

-isotope-dilution mass spectrometry methods are increasingly used for pre-market validation of routine diagnostic assays (these tests also involve substantial sets of clinical validation samples). Based on this definition/terminology, we list recognized causes of irregular analytical error as a risk catalog for clinical chemistry in this article. These issues include reproducible individual analytical errors (e.g. caused by anti-reagent antibodies) and non-reproducible, sporadic errors (e.g. errors due to incorrect pipetting volume due to air bubbles in a sample), which can both lead to inaccurate results and risks for patients.

Divergence-based tests for model diagnostic

Czech Academy of Sciences Publication Activity Database

Hobza, Tomáš; Esteban, M. D.; Morales, D.; Marhuenda, Y.

2008-01-01

Roč. 78, č. 13 (2008), s. 1702-1710 ISSN 0167-7152 R&D Projects: GA MŠk 1M0572 Grant - others:Instituto Nacional de Estadistica (ES) MTM2006-05693 Institutional research plan: CEZ:AV0Z10750506 Keywords : goodness of fit * devergence statistics * GLM * model checking * bootstrap Subject RIV: BB - Applied Statistics, Operational Research Impact factor: 0.445, year: 2008 http://library.utia.cas.cz/separaty/2008/SI/hobza-divergence-based%20tests%20for%20model%20diagnostic.pdf

Microbiopsy a first-level diagnostic test to rule out oral dysplasia or carcinoma in general dental practice.

Science.gov (United States)

Pentenero, M; Val, M; Rosso, S; Gandolfo, S

2018-03-01

Diagnostic delay in oral oncology could be improved if general dentists had a reliable and easy-to-use first-level diagnostic test to rule out the presence of oral dysplasia or carcinoma. Microbiopsy has been proved to have high sensitivity and high negative predictive value in a clinical setting characterized by high prevalence of disease. Moreover, it has been proved to be easily performed by general dentists. This study aimed to determine the negative predictive value of microbiopsy in routine dental practice: a clinical setting characterized by low prevalence of disease. Within the frame of a previous study, general dentists from the Metropolitan Area of Turin performed microbiopsy for each oral mucosal lesion detected during their practice. The clinical outcome of 129 lesions negative at microbiopsy was checked by a query performed through the database of the Piedmont Cancer Registry, covering the population of the Metropolitan Area of Turin, with particular reference to cancer involving the mouth (ICD-10:C03-06). This allowed us to define "true negative" cases and to calculate the negative predictive value of microbiopsy. In a mean follow-up of 7.5 years (range 7-9 years), with a dropout rate of 7.7%, no case of tumour involving the mouth was observed, thus revealing a negative predictive value approaching 100%. Microbiopsy represents an easy-to-use and reliable first-level test able to aid general dentists to select patients requiring an oral medicine assessment in a short time and definitely to avoid diagnostic delay in oncologically relevant oral mucosal lesions. © 2018 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd. All rights reserved.

Concordance between a simpler definition of major depressive disorder and Diagnostic and statistical manual of mental disorders, fourth edition: an independent replication in an outpatient sample.

Science.gov (United States)

Zimmerman, Mark; Emmert-Aronson, Benjamin O; Brown, Timothy A

2011-01-01

The diagnostic and statistical manual of mental disorders, fourth edition (DSM-IV) symptom criteria for major depressive disorder (MDD) are somewhat lengthy with several studies showing that clinicians have difficulty recalling all 9 symptoms. Moreover, the criteria include somatic symptoms that are difficult to apply in patients with medical illnesses. To address these problems, a simpler definition of MDD was developed that did not include the somatic symptoms. Previous reports found high levels of agreement between the simplified and full DSM-IV definition of MDD. However, the same research group has conducted all previous studies of psychiatric patients. The goal of the present study was to determine if a high level of concordance between the 2 definitions would be replicated in an independent setting. We interviewed 2907 psychiatric outpatients presenting for treatment at the Boston University Center for Anxiety and Related Disorders. A trained diagnostic rater administered a semistructured interview and inquired about all symptoms of depression for all patients. A high level of agreement was found between the DSM-IV and the simpler definition of MDD. The absolute level of agreement between the 2 definitions was 95.5% and the κ coefficient was 0.88. Thus, consistent with previous studies, a high level of concordance was found between a simpler definition of MDD and the DSM-IV definition. This new definition offers 2 advantages over the current DSM-IV definition-it is briefer, and it is easier to apply with medically ill patients because it is free of somatic symptoms. Implications of these findings for DSM-5 are discussed. Copyright © 2011 Elsevier Inc. All rights reserved.

Diagnostic validation of selected serological tests for detecting scrub typhus.

Science.gov (United States)

Koraluru, Munegowda; Bairy, Indira; Varma, Muralidhar; Vidyasagar, Sudha

2015-07-01

Clinical diagnosis of scrub typhus is often difficult because the symptoms are very similar to those of other febrile illness such as dengue, leptospirosis, malaria and other viral hemorrhagic fevers. Though better diagnostic tests are available for rickettsial diseases and scrub typhus elsewhere, the Weil-Felix test is still commonly used in India, mainly because microimmunofluorescence assays (M-IFA) were not available in India till recently and relevant staff had insufficient training. The present study was performed to investigate the performance of M-IFA, IgM ELISA, and Weil-Felix test on 546 non-repeated serum samples from subjects suspected of having scrub typhus. One hundred and forty-three of these 546 samples were positive by M-IFA; these cases were also confirmed clinically to have scrub typhus based on their dramatic responses to doxycycline therapy. IgM ELISA was positive in 122 of the 143 M-IFA positive cases and the Weil-Felix test in 96. Though the Weil-Felix test is a heterophile agglutination test, it was found in this study to have good specificity but far too little sensitivity to use as a routine diagnostic test. IgM ELISA can be a good substitute for M-IFA. Incorporation of multiple prototype antigens on M-IFA slides is likely one of the reasons for its superior performance. As newer and better diagnostic assays become available for scrub typhus diagnosis in developed countries, it will be imperative to also use such tests in other endemic countries to prevent over- or under-diagnosis of scrub typhus. © 2015 The Societies and Wiley Publishing Asia Pty Ltd.

Diagnostic Accuracy of Obstructive Airway Adult Test for Diagnosis of Obstructive Sleep Apnea.

Science.gov (United States)

Gasparini, Giulio; Vicini, Claudio; De Benedetto, Michele; Salamanca, Fabrizio; Sorrenti, Giovanni; Romandini, Mario; Bosi, Marcello; Saponaro, Gianmarco; Foresta, Enrico; Laforì, Andreina; Meccariello, Giuseppe; Bianchi, Alessandro; Toraldo, Domenico Maurizio; Campanini, Aldo; Montevecchi, Filippo; Rizzotto, Grazia; Cervelli, Daniele; Moro, Alessandro; Arigliani, Michele; Gobbi, Riccardo; Pelo, Sandro

2015-01-01

The gold standard for the diagnosis of Obstructive Sleep Apnea (OSA) is polysomnography, whose access is however reduced by costs and limited availability, so that additional diagnostic tests are needed. To analyze the diagnostic accuracy of the Obstructive Airway Adult Test (OAAT) compared to polysomnography for the diagnosis of OSA in adult patients. Ninety patients affected by OSA verified with polysomnography (AHI ≥ 5) and ten healthy patients, randomly selected, were included and all were interviewed by one blind examiner with OAAT questions. The Spearman rho, evaluated to measure the correlation between OAAT and polysomnography, was 0.72 (p diagnostic accuracy for the diagnosis of OSA. It has also been shown to be able to discriminate among the different degrees of severity of OSA. Additional large studies aiming to validate this questionnaire as a screening or diagnostic test are needed.

Diagnostic accuracy of physical examination tests of the ankle/foot complex: a systematic review.

Science.gov (United States)

Schwieterman, Braun; Haas, Deniele; Columber, Kirby; Knupp, Darren; Cook, Chad

2013-08-01

Orthopedic special tests of the ankle/foot complex are routinely used during the physical examination process in order to help diagnose ankle/lower leg pathologies. The purpose of this systematic review was to investigate the diagnostic accuracy of ankle/lower leg special tests. A search of the current literature was conducted using PubMed, CINAHL, SPORTDiscus, ProQuest Nursing and Allied Health Sources, Scopus, and Cochrane Library. Studies were eligible if they included the following: 1) a diagnostic clinical test of musculoskeletal pathology in the ankle/foot complex, 2) description of the clinical test or tests, 3) a report of the diagnostic accuracy of the clinical test (e.g. sensitivity and specificity), and 4) an acceptable reference standard for comparison. The quality of included studies was determined by two independent reviewers using the Quality Assessment of Diagnostic Accuracy Studies 2 (QUADAS-2) tool. Nine diagnostic accuracy studies met the inclusion criteria for this systematic review; analyzing a total of 16 special tests of the ankle/foot complex. After assessment using the QUADAS-2, only one study had low risk of bias and low concerns regarding applicability. Most ankle/lower leg orthopedic special tests are confirmatory in nature and are best utilized at the end of the physical examination. Most of the studies included in this systematic review demonstrate notable biases, which suggest that results and recommendations in this review should be taken as a guide rather than an outright standard. There is need for future research with more stringent study design criteria so that more accurate diagnostic power of ankle/lower leg special tests can be determined. 3a.

Integrated Rapid-Diagnostic-Test Reader Platform on a Cellphone

Science.gov (United States)

Mudanyali, Onur; Dimitrov, Stoyan; Sikora, Uzair; Padmanabhan, Swati; Navruz, Isa; Ozcan, Aydogan

2012-01-01

We demonstrate a cellphone based Rapid-Diagnostic-Test (RDT) reader platform that can work with various lateral flow immuno-chromatographic assays and similar tests to sense the presence of a target analyte in a sample. This compact and cost-effective digital RDT reader, weighing only ~65 grams, mechanically attaches to the existing camera unit of a cellphone, where various types of RDTs can be inserted to be imaged in reflection or transmission modes under light-emitting-diode (LED) based illumination. Captured raw images of these tests are then digitally processed (within less than 0.2 sec/image) through a smart application running on the cellphone for validation of the RDT as well as for automated reading of its diagnostic result. The same smart application running on the cellphone then transmits the resulting data, together with the RDT images and other related information (e.g., demographic data) to a central server, which presents the diagnostic results on a world-map through geo-tagging. This dynamic spatio-temporal map of various RDT results can then be viewed and shared using internet browsers or through the same cellphone application. We tested this platform using malaria, tuberculosis (TB) as well as HIV RDTs by installing it on both Android based smart-phones as well as an iPhone. Providing real-time spatio-temporal statistics for the prevalence of various infectious diseases, this smart RDT reader platform running on cellphones might assist health-care professionals and policy makers to track emerging epidemics worldwide and help epidemic preparedness. PMID:22596243

A comparison of diagnostic tests for lactose malabsorption - which one is the best?

Directory of Open Access Journals (Sweden)

Hovde Øistein

2009-10-01

Full Text Available Abstract Background Perceived milk intolerance is a common complaint, and tests for lactose malabsorption (LM are unreliable. This study assesses the agreement between diagnostic tests for LM and describes the diagnostic properties of the tests. Methods Patients above 18 years of age with suspected LM were included. After oral intake of 25 g lactose, a combined test with measurement of serum glucose (s-glucose and hydrogen (H2 and methane (CH4 in expired air was performed and symptoms were recorded. In patients with discrepancies between the results, the combined test was repeated and a gene test for lactose non-persistence was added. The diagnosis of LM was based on an evaluation of all tests. The following tests were compared: Increase in H2, CH4, H2+CH4 and H2+CH4x2 in expired air, increase in s-glucose, and symptoms. The agreement was calculated and the diagnostic properties described. Results Sixty patients were included, seven (12% had LM. The agreement (kappa-values between the methods varied from 0.25 to 0.91. The best test was the lactose breath test with measurement of the increase in H2 + CH4x2 in expired air. With a cut-off level Conclusion The agreement between commonly used methods for the diagnosis of LM was unsatisfactory. A lactose breath test with measurement of H2 + CH4x2 in expired air had the best diagnostic properties.

The role of molecular diagnostic testing in the management of thyroid nodules.

Science.gov (United States)

Moore, Maureen D; Panjwani, Suraj; Gray, Katherine D; Finnerty, Brendan M; Zarnegar, Rasa; Fahey, Thomas J

2017-06-01

Fine needle aspiration (FNA) with cytologic examination remains the standard of care for investigation of thyroid nodules. However, as many as 30% of FNA samples are cytologically indeterminate for malignancy, which confounds clinical management. To reduce the burden of repeat diagnostic testing and unnecessary surgery, there has been extensive investigation into molecular markers that can be detected on FNA specimens to more accurately stratify a patient's risk of malignancy. Areas covered: In this review, the authors discuss recent evidence and progress in molecular markers used in the diagnosis of thyroid cancer highlighting somatic gene alterations, molecular technologies and microRNA analysis. Expert commentary: The goal of molecular markers is to improve diagnostic accuracy and aid clinicians in the preoperative management of thyroid lesions. Modalities such as direct mutation analysis, mRNA gene expression profiling, next-generation sequencing, and miRNA expression profiling have been explored to improve the diagnostic accuracy of thyroid nodule FNA. Although no perfect test has been discovered, molecular diagnostic testing has revolutionized the management of thyroid nodules.

Concordance in diagnostic testing for respiratory pathogens of bighorn sheep

Science.gov (United States)

Walsh, Daniel P.; Cassirer, E. Frances; Bonds, Michael D.; Brown, Daniel R.; Edwards, William H.; Weiser, Glen C.; Drew, Mark L.; Briggs, Robert E.; Fox, Karen A.; Miller, Michael W.; Shanthalingam, Sudarvili; Srikumaran, Subramaniam; Besser, Thomas E.

2016-01-01

Reliable diagnostic tests are essential for disease investigation and management. This is particularly true for diseases of free-ranging wildlife where sampling is logistically difficult precluding retesting. Clinical assays for wildlife diseases frequently vary among laboratories because of lack of appropriate standardized commercial kits. Results of diagnostic testing may also be called into question when investigators report different etiologies for disease outbreaks, despite similar clinical and pathologic findings. To evaluate reliability of diagnostic testing for respiratory pathogens of bighorn sheep (Ovis canadensis), we conducted a series of ring tests across 6 laboratories routinely involved in detection of Mycoplasma ovipneumoniae, Pasteurellaceae, lktA (the Pasteurellaceae gene encoding leukotoxin), and 3 reference laboratories. Consistency of results for replicate samples within laboratories was high (median agreement = 1.0). Agreement between laboratories was high for polymerase chain reaction (PCR) detection of M. ovipneumoniae and culture isolation of Mannheimia spp. and Bibersteinia trehalosi(median agreement = 0.89–0.95, Kappa = 0.65–0.74), and lower for PCR detection of Mannheimiaspp. lktA (median agreement = 0.58, Kappa = 0.12). Most errors on defined status samples were false negatives, suggesting test sensitivity was a greater problem than specificity. However, tests for M. haemolytica and lktA yielded some false positive results. Despite differences in testing protocols, median agreement among laboratories and correct classification of controls for most agents was ≥0.80, meeting or exceeding the standard required by federal proficiency testing programs. This information is valuable for interpreting test results, laboratory quality assessments, and advancing diagnosis of respiratory disease in wild sheep. Published 2016. This article is a U.S. Government work and is in the public domain in the USA.

A systematic review of the diagnostic performance of orthopedic physical examination tests of the hip.

Science.gov (United States)

Rahman, Labib Ataur; Adie, Sam; Naylor, Justine Maree; Mittal, Rajat; So, Sarah; Harris, Ian Andrew

2013-08-30

Previous reviews of the diagnostic performances of physical tests of the hip in orthopedics have drawn limited conclusions because of the low to moderate quality of primary studies published in the literature. This systematic review aims to build on these reviews by assessing a broad range of hip pathologies, and employing a more selective approach to the inclusion of studies in order to accurately gauge diagnostic performance for the purposes of making recommendations for clinical practice and future research. It specifically identifies tests which demonstrate strong and moderate diagnostic performance. A systematic search of Medline, Embase, Embase Classic and CINAHL was conducted to identify studies of hip tests. Our selection criteria included an analysis of internal and external validity. We reported diagnostic performance in terms of sensitivity, specificity, predictive values and likelihood ratios. Likelihood ratios were used to identify tests with strong and moderate diagnostic utility. Only a small proportion of tests reported in the literature have been assessed in methodologically valid primary studies. 16 studies were included in our review, producing 56 independent test-pathology combinations. Two tests demonstrated strong clinical utility, the patellar-pubic percussion test for excluding radiologically occult hip fractures (negative LR 0.05, 95% Confidence Interval [CI] 0.03-0.08) and the hip abduction sign for diagnosing sarcoglycanopathies in patients with known muscular dystrophies (positive LR 34.29, 95% CI 10.97-122.30). Fifteen tests demonstrated moderate diagnostic utility for diagnosing and/or excluding hip fractures, symptomatic osteoarthritis and loosening of components post-total hip arthroplasty. We have identified a number of tests demonstrating strong and moderate diagnostic performance. These findings must be viewed with caution as there are concerns over the methodological quality of the primary studies from which we have extracted our

Diagnostic performance of CT angiography in patients visiting emergency department with overt gastrointestinal bleeding

International Nuclear Information System (INIS)

Kim, Ji Hang; Kim, Young Hoon; Lee, Kyoung Ho; Lee, Yoon Jin; Park, Ji Hoon

2015-01-01

To investigate the diagnostic performance of computed tomography angiography (CTA) in identifying the cause of bleeding and to determine the clinical features associated with a positive test result of CTA in patients visiting emergency department with overt gastrointestinal (GI) bleeding. We included 111 consecutive patients (61 men and 50 women; mean age: 63.4 years; range: 28-89 years) who visited emergency department with overt GI bleeding. They underwent CTA as a first-line diagnostic modality from July through December 2010. Two radiologists retrospectively reviewed the CTA images and determined the presence of any definite or potential bleeding focus by consensus. An independent assessor determined the cause of bleeding based on other diagnostic studies and/or clinical follow-up. The diagnostic performance of CTA and clinical characteristics associated with positive CTA results were analyzed. To identify a definite or potential bleeding focus, the diagnostic yield of CTA was 61.3% (68 of 111). The overall sensitivity, specificity, positive predictive value (PPV), and negative predictive value were 84.8% (67 of 79), 96.9% (31 of 32), 98.5% (67 of 68), and 72.1% (31 of 43), respectively. Positive CTA results were associated with the presence of massive bleeding (p = 0.001, odds ratio: 11.506). Computed tomography angiography as a first-line diagnostic modality in patients presenting with overt GI bleeding showed a fairly high accuracy. It could identify definite or potential bleeding focus with a moderate diagnostic yield and a high PPV. CTA is particularly useful in patients with massive bleeding.

The two most popular malnutrition screening tools in the light of the new ESPEN consensus definition of the diagnostic criteria for malnutrition.

Science.gov (United States)

Poulia, Kalliopi-Anna; Klek, Stanislaw; Doundoulakis, Ioannis; Bouras, Emmanouil; Karayiannis, Dimitrios; Baschali, Aristea; Passakiotou, Marili; Chourdakis, Michael

2017-08-01

The new definition of malnutrition in adults proposed recently by The European Society for Clinical Nutrition and Metabolism (ESPEN) changed the view on the issue and raised the question of the reliability of available diagnostic tools. Therefore, the aim of this study was to verify the accuracy of the two most commonly used screening tools by comparing their findings with the new ESPEN criteria. Nutritional screening was performed in 1146 (median age 60 years, interquartile range: 44-73 years, 617 males, 529 females) patients on admission to hospitals with two nutritional screening tools: Nutritional Risk Screening 2002 (NRS2002) and Malnutrition Universal Screening Tool (MUST). The screening results were then compared to the ESPEN new diagnostic criteria for malnutrition. According to the NRS2002 13.5% and 27.9% of the outpatients and hospitalized patients respectively were found to be at moderate/high risk of malnutrition. With the use of MUST 9.1% and 14.9% of the outpatients and hospitalized patients respectively were found to be at moderate/high risk of malnutrition. According to the ESPEN diagnostic criteria 6.4% and 11.3% of outpatients and hospitalized patients respectively were classified as malnourished. MUST was found to be better correlated to the latter for both outpatients (K = 0.777, p malnutrition screening tool in the light of the new ESPEN definition for malnutrition. According to our results, MUST was better correlated with ESPEN criteria for the definition of malnutrition, leading us to the conclusion that it can more efficiently identify the malnourished patients, during the screening process. Copyright © 2016 Elsevier Ltd and European Society for Clinical Nutrition and Metabolism. All rights reserved.

Quality of information accompanying on-line marketing of home diagnostic tests.

Science.gov (United States)

Datta, Adrija K; Selman, Tara J; Kwok, Tony; Tang, Teresa; Khan, Khalid S

2008-01-01

To assess the quality of information provided to consumers by websites marketing medical home diagnostic tests. A cross-sectional analysis of a database developed from searching targeted websites. Data sources were websites written in English which marketed medical home diagnostic tests. A meta-search engine was used to identify the first 20 citations for each type of home diagnostic medical test. Relevant websites limited to those written in English were reviewed independently and in triplicate, with disputes resolved by two further reviewers. Information on the quality of these sites was extracted using a pre-piloted performer. 168 websites were suitable for inclusion in the review. The quality of these sites showed marked variation. Only 24 of 168 (14.2%) complied with at least three-quarters of the quality items and just over half (95 of 168, 56.5%) reported official approval or certification of the test. Information on accuracy of the test marketed was reported by 87 of 168 (51.7%) websites, with 15 of 168 (8.9%) providing a scientific reference. Instructions for use of the product were found in 97 of 168 (57.9%). However, the course of action to be taken after obtaining the test result was stated in only 63 of 168 (37.5%) for a positive result and 43 of 168 (25.5%) for a negative result. The quality of information posted on commercial websites marketing home tests online is unsatisfactory and potentially misleading for consumers.

Evidence Based Medicine; Positive and Negative Likelihood Ratios of Diagnostic Tests

Directory of Open Access Journals (Sweden)

Alireza Baratloo

2015-10-01

Full Text Available In the previous two parts of educational manuscript series in Emergency, we explained some screening characteristics of diagnostic tests including accuracy, sensitivity, specificity, and positive and negative predictive values. In the 3rd  part we aimed to explain positive and negative likelihood ratio (LR as one of the most reliable performance measures of a diagnostic test. To better understand this characteristic of a test, it is first necessary to fully understand the concept of sensitivity and specificity. So we strongly advise you to review the 1st part of this series again. In short, the likelihood ratios are about the percentage of people with and without a disease but having the same test result. The prevalence of a disease can directly influence screening characteristics of a diagnostic test, especially its sensitivity and specificity. Trying to eliminate this effect, LR was developed. Pre-test probability of a disease multiplied by positive or negative LR can estimate post-test probability. Therefore, LR is the most important characteristic of a test to rule out or rule in a diagnosis. A positive likelihood ratio > 1 means higher probability of the disease to be present in a patient with a positive test. The further from 1, either higher or lower, the stronger the evidence to rule in or rule out the disease, respectively. It is obvious that tests with LR close to one are less practical. On the other hand, LR further from one will have more value for application in medicine. Usually tests with 0.1 < LR > 10 are considered suitable for implication in routine practice.

Triple Test in Carcinoma Breast

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Sameer; Mukherjee, Arindam

2014-01-01

Introduction: The commonest clinical presentation in majority of breast pathology is a lump. A definite diagnosis of breast lump is very important for the surgeon to decide on the final course of treatment and also saves the patient from unnecessary physical, emotional and psychological trauma if there is a definite preoperative diagnosis of benign lesion. The present study was done to evaluate the effectiveness and relevance of “TRIPLE TEST”in diagnosis of carcinoma breast in rural labour class population. Materials and Methods: The present study was a prospective study conducted on patients over 35 years of age having palpable breast lumps presenting in the out patient department of general surgery, ESI Hospital Basaidarapur New Delhi, India. The duration of study was from May 2007 to June 2009 and a total of 100 cases were studied. Each patient was subjected to a detailed history, clinical breast examination ,diagnostic mammography and FNAC. In this study, the results of each modality was divided in three groups: benign, suspicious and malignant. The sensitivity, specificity, positive predictive value, negative predictive value and diagnostic accuracy of each test was calculated individually and as combined. Result: Out of 100 patients enrolled in this study, 60 cases were benign and 40 cases were of malignant breast disease. The age of patients with carcinoma breast in the series varied from 35 years to 70 years. The highest incidence of malignancy noted was 30% in 41-50 years age group (4th decade) followed by 27.5% in 51-60 years age group (5th decade). The sensitivity of clinical examination was found to be 75%, specificity was 83.3%, positive predictive value (PPV) of 75% and diagnostic accuracy of 80%. The sensitivity, specificity, positive predictive value and diagnostic accuracy of mammography was calculated and was found to be 94.9% , 90% , 86% and 92% respectively. The sensitivity, specificity, positive predictive value and diagnostic accuracy of

The Evaluation of Diagnostic Tests for Sexually Transmitted Infections

Directory of Open Access Journals (Sweden)

Max A Chernesky

2005-01-01

Full Text Available Diagnostic tests should receive method- and use-effectiveness evaluations. Method-effectiveness evaluations determine sensitivity, specificity and predictive values for new tests. Use-effectiveness evaluations determine how practical or convenient a new test will be in a specific setting and may not be performed in a formal way in North American laboratories. To perform a clinical method evaluation of diagnostic tests, a good relationship between laboratory and clinical personnel is essential. Studies are usually conducted separately on populations of men and women, and should include sampling from different prevalence groups. Test performance comparisons may be made on a single specimen type or on more than one specimen from the same patient, which allows for the expansion of a reference standard and includes the ability of a particular assay, performed on a specimen type to diagnose an infected individual. The following components of the evaluation should be standardized and carefully followed: specimen identification; collection; transportation; processing; quality control; reading; proficiency testing; confirmatory testing; discordant analysis -- sensitivity, specificity and predictive value calculations; and record keeping. Methods are available to determine whether sample results are true or false positives or negatives. Use-effectiveness evaluations might determine the stability or durability of supplies and equipment; the logistics of shipping, receiving and storing supplies; the clarity and completeness of test instructions; the time and effort required to process and read results; the subjectivity factors in interpretation and reporting; and the costs. These determinations are usually more apparent for commercial assays than for homemade tests.

Diagnostic Tests for Entering and Departing Undergraduate Students

Science.gov (United States)

Waltham, Chris; Kotlicki, A.

2006-12-01

A diagnostic test administered at the start of a class should test basic concepts which are recognized as course prerequisites. The questions should not be over-packaged: e.g. students should be required to create models, rather than this being done for them each time. Students should be allowed great latitude in their answers, so we can discover what they are thinking. When administered at the end of a class the goals should be similar: testing concepts taught in the class itself and the retention of necessary concepts from previous classes. Great care has to be taken to avoid teaching to the test. In assessing an entire program, for example an undergraduate majors degree in physics, then one looks for very general skills and knowledge not specific to any one course. The purpose of an undergraduate degree in physics (or indeed any science) is to equip the students with a set of problem-solving skills and basic knowledge which can be applied in a large variety of workplace settings and to allow that student to contribute to civic society as a science-literate person. The creator of any diagnostic test should always have these big goals in mind. We have developed a set of questions which we think fulfill these criteria, yet are not specific to any particular level of science education. They have been administered to students in secondary schools across Canada, incoming first-year science students and final-year physics students at the University of British Columbia. The results will be presented.

Beyond the 2×2 -contingency table: a primer on entropies and mutual information in various scenarios involving m diagnostic categories and n categories of diagnostic tests.

Science.gov (United States)

Reibnegger, Gilbert

2013-10-21

Usual evaluation tools for diagnostic tests such as, sensitivity/specificity and ROC analyses, are designed for the discrimination between two diagnostic categories, using dichotomous test results. Information theoretical quantities such as mutual information allow in depth-analysis of more complex discrimination problems, including continuous test results, but are rarely used in clinical chemistry. This paper provides a primer on useful information theoretical concepts with a strong focus on typical diagnostic scenarios. Information theoretical concepts are shortly explained. Mathematica CDF documents are provided which compute entropies and mutual information as function of pretest probabilities and the distribution of test results among the categories, and allow interactive exploration of the behavior of these quantities in comparison with more conventional diagnostic measures. Using data from a previously published study, the application of information theory to practical diagnostic problems involving up to 4×4 -contingency tables is demonstrated. Information theoretical concepts are particularly useful for diagnostic problems requiring more than the usual binary classification. Quantitative test results can be properly analyzed, and in contrast to popular concepts such as ROC analysis, the effects of variations of pre-test probabilities of the diagnostic categories can be explicitly taken into account. © 2013 Elsevier B.V. All rights reserved.

Costs of genetic testing: Supporting Brazilian Public Policies for the incorporating of molecular diagnostic technologies

Directory of Open Access Journals (Sweden)

Rosane Paixão Schlatter

2015-09-01

Full Text Available This study identifies and describes the operating costs associated with the molecular diagnosis of diseases, such as hereditary cancer. To approximate the costs associated with these tests, data informed by Standard Operating Procedures for various techniques was collected from hospital software and a survey of market prices. Costs were established for four scenarios of capacity utilization to represent the possibility of suboptimal use in research laboratories. Cost description was based on a single site. The results show that only one technique was not impacted by rising costs due to underutilized capacity. Several common techniques were considerably more expensive at 30% capacity, including polymerase chain reaction (180%, microsatellite instability analysis (181%, gene rearrangement analysis by multiplex ligation probe amplification (412%, non-labeled sequencing (173%, and quantitation of nucleic acids (169%. These findings should be relevant for the definition of public policies and suggest that investment of public funds in the establishment of centralized diagnostic research centers would reduce costs to the Public Health System.

Identification student’s misconception of heat and temperature using three-tier diagnostic test

Science.gov (United States)

Suliyanah; Putri, H. N. P. A.; Rohmawati, L.

2018-03-01

The objective of this research is to develop a Three-Tier Diagnostic Test (TTDT) to identify the student's misconception of heat and temperature. Stages of development include: analysis, planning, design, development, evaluation and revise. The results of this study show that (1) the quality of the three-tier type diagnostic test instrument developed has been expressed well with the following details: (a) Internal validity of 88.19% belonging to the valid category. (b) External validity of empirical construct validity test using Pearson Product Moment obtained 0.43 is classified and result of empirical construct validity test obtained false positives 6.1% and false negatives 5.9% then the instrument was valid. (c) Test reliability by using Cronbach’s Alpha of 0.98 which means acceptable. (d) The 80% difficulty level test is quite difficult. (2) Student misconceptions on the temperature of heat and displacement materials based on the II test the highest (84%), the lowest (21%), and the non-misconceptions (7%). (3) The highest cause of misconception among students is associative thinking (22%) and the lowest is caused by incomplete or incomplete reasoning (11%). Three-Tier Diagnostic Test (TTDT) could identify the student's misconception of heat and temperature.

Molecular Tools for Diagnosis of Visceral Leishmaniasis: Systematic Review and Meta-Analysis of Diagnostic Test Accuracy

Science.gov (United States)

de Ruiter, C. M.; van der Veer, C.; Leeflang, M. M. G.; Deborggraeve, S.; Lucas, C.

2014-01-01

Molecular methods have been proposed as highly sensitive tools for the detection of Leishmania parasites in visceral leishmaniasis (VL) patients. Here, we evaluate the diagnostic accuracy of these tools in a meta-analysis of the published literature. The selection criteria were original studies that evaluate the sensitivities and specificities of molecular tests for diagnosis of VL, adequate classification of study participants, and the absolute numbers of true positives and negatives derivable from the data presented. Forty studies met the selection criteria, including PCR, real-time PCR, nucleic acid sequence-based amplification (NASBA), and loop-mediated isothermal amplification (LAMP). The sensitivities of the individual studies ranged from 29 to 100%, and the specificities ranged from 25 to 100%. The pooled sensitivity of PCR in whole blood was 93.1% (95% confidence interval [CI], 90.0 to 95.2), and the specificity was 95.6% (95% CI, 87.0 to 98.6). The specificity was significantly lower in consecutive studies, at 63.3% (95% CI, 53.9 to 71.8), due either to true-positive patients not being identified by parasitological methods or to the number of asymptomatic carriers in areas of endemicity. PCR for patients with HIV-VL coinfection showed high diagnostic accuracy in buffy coat and bone marrow, ranging from 93.1 to 96.9%. Molecular tools are highly sensitive assays for Leishmania detection and may contribute as an additional test in the algorithm, together with a clear clinical case definition. We observed wide variety in reference standards and study designs and now recommend consecutively designed studies. PMID:24829226

Engineering test facility design definition

Science.gov (United States)

Bercaw, R. W.; Seikel, G. R.

1980-01-01

The Engineering Test Facility (ETF) is the major focus of the Department of Energy (DOE) Magnetohydrodynamics (MHD) Program to facilitate commercialization and to demonstrate the commercial operability of MHD/steam electric power. The ETF will be a fully integrated commercial prototype MHD power plant with a nominal output of 200 MW sub e. Performance of this plant is expected to meet or surpass existing utility standards for fuel, maintenance, and operating costs; plant availability; load following; safety; and durability. It is expected to meet all applicable environmental regulations. The current design concept conforming to the general definition, the basis for its selection, and the process which will be followed in further defining and updating the conceptual design.

Quality of information accompanying on-line marketing of home diagnostic tests

Science.gov (United States)

Datta, Adrija K; Selman, Tara J; Kwok, Tony; Tang, Teresa; Khan, Khalid S

2008-01-01

Objective To assess the quality of information provided to consumers by websites marketing medical home diagnostic tests. Design A cross-sectional analysis of a database developed from searching targeted websites. Setting Data sources were websites written in English which marketed medical home diagnostic tests. Main outcome measures A meta-search engine was used to identify the first 20 citations for each type of home diagnostic medical test. Relevant websites limited to those written in English were reviewed independently and in triplicate, with disputes resolved by two further reviewers. Information on the quality of these sites was extracted using a pre-piloted performer. Results 168 websites were suitable for inclusion in the review. The quality of these sites showed marked variation. Only 24 of 168 (14.2%) complied with at least three-quarters of the quality items and just over half (95 of 168, 56.5%) reported official approval or certification of the test. Information on accuracy of the test marketed was reported by 87 of 168 (51.7%) websites, with 15 of 168 (8.9%) providing a scientific reference. Instructions for use of the product were found in 97 of 168 (57.9%). However, the course of action to be taken after obtaining the test result was stated in only 63 of 168 (37.5%) for a positive result and 43 of 168 (25.5%) for a negative result. Conclusions The quality of information posted on commercial websites marketing home tests online is unsatisfactory and potentially misleading for consumers. PMID:18263912

Diagnostic significance of haematological testing in patients presenting at the Emergency Department

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Giuseppe Lippi

2012-03-01

Full Text Available The use of simple and economic tests to rule out diseases of sufficient clinical severity is appealing in emergency department (ED, since it would be effective for contrasting ED overcrowding and decreasing healthcare costs. The aim of this study was to assess the diagnostic performance of simple and economic haematological testing in a large sample of adult patients presenting at the ED of the Academic Hospital of Parma during the year 2010 with the five most frequent acute pathologies (i.e., acute myocardial infarction, renal colic, pneumonia, trauma and pancreatitis. Both leukocyte count and hemoglobin showed a good diagnostic performance (Area Under the Curve [AUC] of 0.85 for leukocyte count and 0.76 for hemoglobin; both p < 0.01. Although the platelet count was significantly increased in all patients groups except pancreatitis, the diagnostic performance did not achieve statistical significance (AUC 0.53; p = 0.07. We also observed an increased RDW in all groups, except in those with trauma and the diagnostic performance was acceptable (AUC 0.705; p < 0.01. The mean platelet volume (MPV was consistently lower in all patients groups and also characterized by an efficient diagnostic performance (AUC 0.76; p < 0.01. This evidence led us to design an arbitrary formula, whereby MPV and hemoglobin were multiplied, and further divided by the leukocyte count, obtaining a remarkable AUC (0.91; p < 0.01. We conclude that simple, rapid and cheap hematological tests might provide relevant clinical information for decision making to busy emergency physicians, and the their combination into an arbitrary formula might further increase the specific diagnostic potential of each of them.

Auditory Automotive Mechanics Diagnostic Achievement Test. Center Technical Paper No. 2.

Science.gov (United States)

Swanson, Richard Arthur

The Auditory Automotive Mechanics Diagnostic Achievement Test assesses an automobile mechanic's ability to determine mechanical faults from auditory cues alone. The 44-item test and its instructions are recorded on magnetic tape; answer choices are presented on tape, and are also written in the printed test booklets. The norming and validity…

Performance Evaluation of Commercial Dengue Diagnostic Tests for Early Detection of Dengue in Clinical Samples

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Tuan Nur Akmalina Mat Jusoh

2017-01-01

Full Text Available The shattering rise in dengue virus infections globally has created a need for an accurate and validated rapid diagnostic test for this virus. Rapid diagnostic test (RDT and reverse transcription-polymerase chain reaction (RT-PCR diagnostic detection are useful tools for diagnosis of early dengue infection. We prospectively evaluated the diagnostic performance of nonstructural 1 (NS1 RDT and real-time RT-PCR diagnostic kits in 86 patient serum samples. Thirty-six samples were positive for dengue NS1 antigen while the remaining 50 were negative when tested with enzyme-linked immunosorbent assay (ELISA. Commercially available RDTs for NS1 detection, RTK ProDetect™, and SD Bioline showed high sensitivity of 94% and 89%, respectively, compared with ELISA. GenoAmp® Trioplex Real-Time RT-PCR and RealStar® Dengue RT-PCR tests presented a comparable kappa agreement with 0.722. The result obtained from GenoAmp® Real-Time RT-PCR Dengue test showed that 14 samples harbored dengue virus type 1 (DENV-1, 8 samples harbored DENV-2, 2 samples harbored DENV-3, and 1 sample harbored DENV-4. 1 sample had a double infection with DENV-1 and DENV-2. The NS1 RDTs and real-time RT-PCR tests were found to be a useful diagnostic for early and rapid diagnosis of acute dengue and an excellent surveillance tool in our battle against dengue.

Diagnostic and laboratory test ordering in Northern Portuguese Primary Health Care: a cross-sectional study

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Sá, Luísa; Teixeira, Andreia Sofia Costa; Tavares, Fernando; Costa-Santos, Cristina; Couto, Luciana; Costa-Pereira, Altamiro; Hespanhol, Alberto Pinto; Santos, Paulo

2017-01-01

Objectives To characterise the test ordering pattern in Northern Portugal and to investigate the influence of context-related factors, analysing the test ordered at the level of geographical groups of family physicians and at the level of different healthcare organisations. Design Cross-sectional study. Setting Northern Primary Health Care, Portugal. Participants Records about diagnostic and laboratory tests ordered from 2035 family physicians working at the Northern Regional Health Administration, who served approximately 3.5 million Portuguese patients, in 2014. Outcomes To determine the 20 most ordered diagnostic and laboratory tests in the Northern Regional Health Administration; to identify the presence and extent of variations in the 20 most ordered diagnostic and laboratory tests between the Groups of Primary Care Centres and between health units; and to study factors that may explain these variations. Results The 20 most ordered diagnostic and laboratory tests almost entirely comprise laboratory tests and account for 70.9% of the total tests requested. We can trace a major pattern of test ordering for haemogram, glucose, lipid profile, creatinine and urinalysis. There was a significant difference (P<0.001) in test orders for all tests between Groups of Primary Care Centres and for all tests, except glycated haemoglobin (P=0.06), between health units. Generally, the Personalised Healthcare Units ordered more than Family Health Units. Conclusions The results from this study show that the most commonly ordered tests in Portugal are laboratory tests, that there is a tendency for overtesting and that there is a large variability in diagnostic and laboratory test ordering in different geographical and organisational Portuguese primary care practices, suggesting that there may be considerable potential for the rationalisation of test ordering. The existence of Family Health Units seems to be a strong determinant in decreasing test ordering by Portuguese family

The impact of communication barriers on diagnostic confidence and ancillary testing in the emergency department.

Science.gov (United States)

Garra, Gregory; Albino, Hiram; Chapman, Heather; Singer, Adam J; Thode, Henry C

2010-06-01

Communication barriers (CBs) compromise the diagnostic power of the medical interview and may result in increased reliance on diagnostic tests or incorrect test ordering. The prevalence and degree to which these barriers affect diagnosis, testing, and treatment are unknown. To quantify and characterize CBs encountered in the Emergency Department (ED), and assess the effect of CBs on initial diagnosis and perceived reliance on ancillary testing. This was a prospective survey completed by emergency physicians after initial adult patient encounters. CB severity, diagnostic confidence, and reliance on ancillary testing were quantified on a 100-mm Visual Analog Scale (VAS) from least (0) to most (100). Data were collected on 417 ED patient encounters. CBs were reported in 46%; with a mean severity of 50 mm on a 100-mm VAS with endpoints of "perfect communication and "no communication." Language was the most commonly reported form of CB (28%). More than one CB was identified in 6%. The 100-mm VAS rating of diagnostic confidence was lower in patients with perceived CBs (64 mm) vs. those without CBs (80 mm), p Communication barriers in our ED setting were common, and resulted in lower diagnostic confidence and increased perception that ancillary tests are needed to narrow the diagnosis. Copyright 2010 Elsevier Inc. All rights reserved.

Mirror fusion test facility plasma diagnostics system

International Nuclear Information System (INIS)

Thomas, S.R. Jr.; Coffield, F.E.; Davis, G.E.; Felker, B.

1979-01-01

During the past 25 years, experiments with several magnetic mirror machines were performed as part of the Magnetic Fusion Energy (MFE) Program at LLL. The latest MFE experiment, the Mirror Fusion Test Facility (MFTF), builds on the advances of earlier machines in initiating, stabilizing, heating, and sustaining plasmas formed with deuterium. The goals of this machine are to increase ion and electron temperatures and show a corresponding increase in containment time, to test theoretical scaling laws of plasma instabilities with increased physical dimensions, and to sustain high-beta plasmas for times that are long compared to the energy containment time. This paper describes the diagnostic system being developed to characterize these plasma parameters

Molecular diagnostics for human leptospirosis.

Science.gov (United States)

Waggoner, Jesse J; Pinsky, Benjamin A

2016-10-01

The definitive diagnosis of leptospirosis, which results from infection with spirochetes of the genus Leptospira, currently relies on the use of culture, serological testing (microscopic agglutination testing), and molecular detection. The purpose of this review is to describe new molecular diagnostics for Leptospira and discuss advancements in the use of available methods. Efforts have been focused on improving the clinical sensitivity of Leptospira detection using molecular methods. In this review, we describe a reoptimized pathogenic species-specific real-time PCR (targeting lipL32) that has demonstrated improved sensitivity, findings by two groups that real-time reverse-transcription PCR assays targeting the 16S rrs gene can improve detection, and two new loop-mediated amplification techniques. Quantitation of leptospiremia, detection in different specimen types, and the complementary roles played by molecular detection and microscopic agglutination testing will be discussed. Finally, a protocol for Leptospira strain subtyping using variable number tandem repeat targets and high-resolution melting will be described. Molecular diagnostics have an established role for the diagnosis of leptospirosis and provide an actionable diagnosis in the acute setting. The use of real-time reverse-transcription PCR for testing serum/plasma and cerebrospinal fluid, when available, may improve the detection of Leptospira without decreasing clinical specificity.

Diagnostic criteria for hereditary hemorrhagic telangiectasia (Rendu-Osler-Weber syndrome)

DEFF Research Database (Denmark)

Shovlin, C L; Guttmacher, A E; Buscarini, E

2000-01-01

Hereditary Hemorrhagic Telangiectasia (HHT) is easily recognized in individuals displaying the classical triad of epistaxis, telangiectasia, and a suitable family history, but the disease is more difficult to diagnosis in many patients. Serious consequences may result if visceral arteriovenous ma...... in this disorder. These criteria may be refined as molecular diagnostic tests become available in the next few years....... of the HHT Foundation International, Inc., we present consensus clinical diagnostic criteria. The four criteria (epistaxes, telangiectasia, visceral lesions and an appropriate family history) are carefully delineated. The HHT diagnosis is definite if three criteria are present. A diagnosis of HHT cannot...

Development of a molecular diagnostic test for Retinitis Pigmentosa in the Japanese population.

Science.gov (United States)

Maeda, Akiko; Yoshida, Akiko; Kawai, Kanako; Arai, Yuki; Akiba, Ryutaro; Inaba, Akira; Takagi, Seiji; Fujiki, Ryoji; Hirami, Yasuhiko; Kurimoto, Yasuo; Ohara, Osamu; Takahashi, Masayo

2018-05-21

Retinitis Pigmentosa (RP) is the most common form of inherited retinal dystrophy caused by different genetic variants. More than 60 causative genes have been identified to date. The establishment of cost-effective molecular diagnostic tests with high sensitivity and specificity can be beneficial for patients and clinicians. Here, we developed a clinical diagnostic test for RP in the Japanese population. Evaluation of diagnostic technology, Prospective, Clinical and experimental study. A panel of 39 genes reported to cause RP in Japanese patients was established. Next generation sequence (NGS) technology was applied for the analyses of 94 probands with RP and RP-related diseases. After interpretation of detected genetic variants, molecular diagnosis based on a study of the genetic variants and a clinical phenotype was made by a multidisciplinary team including clinicians, researchers and genetic counselors. NGS analyses found 14,343 variants from 94 probands. Among them, 189 variants in 83 probands (88.3% of all cases) were selected as pathogenic variants and 64 probands (68.1%) have variants which can cause diseases. After the deliberation of these 64 cases, molecular diagnosis was made in 43 probands (45.7%). The final molecular diagnostic rate with the current system combining supplemental Sanger sequencing was 47.9% (45 of 94 cases). The RP panel provides the significant advantage of detecting genetic variants with a high molecular diagnostic rate. This type of race-specific high-throughput genotyping allows us to conduct a cost-effective and clinically useful genetic diagnostic test.

Alternative diagnostic technique for carpal tunnel syndrome

International Nuclear Information System (INIS)

Hayakawa, Katsuhiko; Nakane, Takashi; Kobayashi, Shigeru; Shibata, Kunio

2002-01-01

Compressive and entrapment neuropathies are common clinical syndromes characterized by neurologic deficits due to mechanical or dynamic compression of peripheral nerves. However, the definitive diagnosis based on clinical symptoms alone is difficult in many cases, and the electrophysiological diagnostic method is solely used as a supplementary diagnostic method at present. As a new diagnostic method for entrapment neuropathy, the present study investigated the usefulness of gadolinium-enhanced MRI in carpal tunnel syndrome. On enhanced MRI of idiopathic carpal tunnel syndrome, contrast-enhancement in the median nerve was found in 30 of 34 hands (88.2%). Enhanced MRI allows to visualize intraneural edema in the nerve easily on the naked eye. Therefore, this technique supplied useful information for making definitive diagnosis and is promising as a non-invasive diagnostic method for entrapment neuropathy. (author)

Alternative diagnostic technique for carpal tunnel syndrome

Energy Technology Data Exchange (ETDEWEB)

Hayakawa, Katsuhiko; Nakane, Takashi [Aiko Orthopaedic Hospital, Nagoya (Japan); Kobayashi, Shigeru; Shibata, Kunio [Fujita Health Univ., Toyoake, Aichi (Japan). School of Medicine

2002-10-01

Compressive and entrapment neuropathies are common clinical syndromes characterized by neurologic deficits due to mechanical or dynamic compression of peripheral nerves. However, the definitive diagnosis based on clinical symptoms alone is difficult in many cases, and the electrophysiological diagnostic method is solely used as a supplementary diagnostic method at present. As a new diagnostic method for entrapment neuropathy, the present study investigated the usefulness of gadolinium-enhanced MRI in carpal tunnel syndrome. On enhanced MRI of idiopathic carpal tunnel syndrome, contrast-enhancement in the median nerve was found in 30 of 34 hands (88.2%). Enhanced MRI allows to visualize intraneural edema in the nerve easily on the naked eye. Therefore, this technique supplied useful information for making definitive diagnosis and is promising as a non-invasive diagnostic method for entrapment neuropathy. (author)

Inventions leading to the development of the diagnostic test kit industry--from the modern pregnancy test to the sandwich assays.

Science.gov (United States)

Wide, Leif

2005-01-01

The universities are encouraged by the government nowadays to stimulate innovations and also to provide the proper machinery for assisting the protection and commercialisation of innovations. A better understanding of the innovation process may help to create an atmosphere suitable for inventions at the university. Examples can be taken from successful innovations previously made at the university. During the 1960's I made a series of inventions, which ultimately led to the development of the diagnostic test kit industry. The first, which I made as an undergraduate, was a simple and reliable test kit for diagnosis of pregnancy. This was followed by the solid phase radioimmunoassay and a solid phase assay for vitamin B12; next, the dual specific non-competitive sandwich assay and the in-vitro test for diagnosis of allergy, called RAST (Radioallergosorbent test). Organon in Holland with the pregnancy test kit, and Pharmacia in Sweden with test kits for radioimmunoassay, became pioneers among the diagnostic test kit industries. Pharmacia Diagnostics later became one of the leading diagnostic test kit companies in the world and has continued to be so in the field of allergy diagnosis. Each one of these inventions started with a few unique observations leading to a technical development. The pregnancy test as well as the allergy test emerged from the development of assay methods with unique qualities with the subsequent search for appropriate applications. The foreseeing of a commercial value on a future market was a very important step. This was followed by the search for a suitable industry interested to exploit the invention with its new business opportunity i.e. apply for a patent, produce and market the products, which in my case consisted of the necessary reagents and equipments for particular diagnostic tests. Finally, an agreement had to be settled between the entrepreneur and the inventors. This report describes these inventions and particularly discusses some

Pre-examination factors affecting molecular diagnostic test results and interpretation: A case-based approach.

Science.gov (United States)

Payne, Deborah A; Baluchova, Katarina; Peoc'h, Katell H; van Schaik, Ron H N; Chan, K C Allen; Maekawa, Masato; Mamotte, Cyril; Russomando, Graciela; Rousseau, François; Ahmad-Nejad, Parviz

2017-04-01

Multiple organizations produce guidance documents that provide opportunities to harmonize quality practices for diagnostic testing. The International Organization for Standardization ISO 15189 standard addresses requirements for quality in management and technical aspects of the clinical laboratory. One technical aspect addresses the complexities of the pre-examination phase prior to diagnostic testing. The Committee for Molecular Diagnostics of the International Federation for Clinical Chemistry and Laboratory Medicine (also known as, IFCC C-MD) conducted a survey of international molecular laboratories and determined ISO 15189 to be the most referenced guidance document. In this review, the IFCC C-MD provides case-based examples illustrating the value of select pre-examination processes as these processes relate to molecular diagnostic testing. Case-based examples in infectious disease, oncology, inherited disease and pharmacogenomics address the utility of: 1) providing information to patients and users, 2) designing requisition forms, 3) obtaining informed consent and 4) maintaining sample integrity prior to testing. The pre-examination phase requires extensive and consistent communication between the laboratory, the healthcare provider and the end user. The clinical vignettes presented in this paper illustrate the value of applying select ISO 15189 recommendations for general laboratory to the more specialized area of Molecular Diagnostics. Copyright © 2016 Elsevier B.V. All rights reserved.

Appraising and applying evidence about a diagnostic test during a performance-based assessment

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Franklin Ellen

2004-10-01

Full Text Available Abstract Background The practice of Evidence-based Medicine requires that clinicians assess the validity of published research and then apply the results to patient care. We wanted to assess whether our soon-to-graduate medical students could appraise and apply research about a diagnostic test within a clinical context and to compare our students with peers trained at other institutions. Methods 4th year medical students who previously had demonstrated competency at probability revision and just starting first-year Internal Medicine residents were used for this research. Following an encounter with a simulated patient, subjects critically appraised a paper about an applicable diagnostic test and revised the patient's pretest probability given the test result. Results The medical students and residents demonstrated similar skills at critical appraisal, correctly answering 4.7 and 4.9, respectively, of 6 questions (p = 0.67. Only one out of 28 (3% medical students and none of the 15 residents were able to correctly complete the probability revision task (p = 1.00. Conclusions This study found that most students completing medical school are able to appraise an article about a diagnostic test but few are able to apply the information from the article to a patient. These findings raise questions about the clinical usefulness of the EBM skills possessed by graduating medical students within the area of diagnostic testing.

Sequential Test Selection by Quantifying of the Reduction in Diagnostic Uncertainty for the Diagnosis of Proximal Caries

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Umut Arslan

2013-06-01

Full Text Available Background: In order to determine the presence or absence of a certain disease, multiple diagnostic tests may be necessary. Performance of these tests can be sequentially evaluated. Aims: The aim of the study is to determine the contribution of the test in each step, in reducing diagnostic uncertainty when multiple tests are sequentially used for the diagnosis. Study Design: Diagnostic accuracy study Methods: Radiographs of seventy-three patients of the Department of Dento-Maxillofacial Radiology of Hacettepe University Faculty of Dentistry were assessed. Panoramic (PAN, full mouth intraoral (FM, and bitewing (BW radiographs were used for the diagnosis of proximal caries in the maxillary and mandibular molar regions. Diagnostic performance of radiography was sequentially evaluated by using the reduction in diagnostic uncertainty. Results: FM provided maximum diagnostic information for ruling in potential in the maxillary and mandibular molar regions in the first step. FM provided more diagnostic information than BW radiographs for ruling in the mandibular region in the second step. In the mandibular region, BW radiographs provided more diagnostic information than FM for ruling out in the first step. Conclusion: The presented method in this study provides the clinicians with a solution for the decision of the sequential selection of diagnostic tests for the correct diagnosis of the presence or absence of a certain disease.

Privacy and equality in diagnostic genetic testing.

Science.gov (United States)

Nyrhinen, Tarja; Hietala, Marja; Puukka, Pauli; Leino-Kilpi, Helena

2007-05-01

This study aimed to determine the extent to which the principles of privacy and equality were observed during diagnostic genetic testing according to views held by patients or child patients' parents (n = 106) and by staff (n = 162) from three Finnish university hospitals. The data were collected through a structured questionnaire and analysed using the SAS 8.1 statistical software. In general, the two principles were observed relatively satisfactorily in clinical practice. According to patients/parents, equality in the post-analytic phase and, according to staff, privacy in the pre-analytic phase, involved the greatest ethical problems. The two groups differed in their views concerning pre-analytic privacy. Although there were no major problems regarding the two principles, the differences between the testing phases require further clarification. To enhance privacy protection and equality, professionals need to be given more genetics/ethics training, and patients individual counselling by genetics units staff, giving more consideration to patients' world-view, the purpose of the test and the test result.

Diagnostic accuracy of scapular physical examination tests for shoulder disorders: a systematic review.

Science.gov (United States)

Wright, Alexis A; Wassinger, Craig A; Frank, Mason; Michener, Lori A; Hegedus, Eric J

2013-09-01

To systematically review and critique the evidence regarding the diagnostic accuracy of physical examination tests for the scapula in patients with shoulder disorders. A systematic, computerised literature search of PubMED, EMBASE, CINAHL and the Cochrane Library databases (from database inception through January 2012) using keywords related to diagnostic accuracy of physical examination tests of the scapula. The Quality Assessment of Diagnostic Accuracy Studies tool was used to critique the quality of each paper. Eight articles met the inclusion criteria; three were considered to be of high quality. Of the three high-quality studies, two were in reference to a 'diagnosis' of shoulder pain. Only one high-quality article referenced specific shoulder pathology of acromioclavicular dislocation with reported sensitivity of 71% and 41% for the scapular dyskinesis and SICK scapula test, respectively. Overall, no physical examination test of the scapula was found to be useful in differentially diagnosing pathologies of the shoulder.

Molecular diagnostics in medical microbiology: yesterday, today and tomorrow.

Science.gov (United States)

van Belkum, Alex

2003-10-01

Clinical microbiology is clearly on the move, and various new diagnostic technologies have been introduced into laboratory practice over the past few decades. However, Henri D Isenberg recently stated that molecular biology techniques promised to revolutionise the diagnosis of infectious disease, but that, to date, this promise is still in its infancy. Molecular diagnostics have now surpassed these early stages and have definitely reached puberty. Currently, a second generation of automated molecular approaches is already within the microbiologists' reach. Quantitative amplification tests in combination with genomics, transcriptomics, proteomics and related methodologies will pave the way to further enhancement of innovative microbial detection and identification.

The evaluation and impact of diagnostic tests

International Nuclear Information System (INIS)

Royal, H.D.; McNeil, B.J.

1989-01-01

The authors describe the usefulness of the techniques that are applied to study the role of tests and point out their limitations. In many instances, complex tasks must be oversimplified in order to use currently available analytic tools. Certain tools, such as decision analysis, are useful not only because they can provide insight regarding the most favorable diagnostic/therapeutic strategies but also because they can identify areas where present knowledge is inadequate and thereby help put priorities on areas of research

75 FR 9953 - Definition and Requirements for a Nationally Recognized Testing Laboratory (NRTL); Extension of...

Science.gov (United States)

2010-03-04

...] Definition and Requirements for a Nationally Recognized Testing Laboratory (NRTL); Extension of the Office of Management and Budget's (OMB) Approval of Information Collection (Paperwork) Requirements AGENCY... its Regulation on the Definition and Requirements for a Nationally Recognized Testing Laboratory (29...

Bayesian analysis of longitudinal Johne's disease diagnostic data without a gold standard test

DEFF Research Database (Denmark)

Wang, C.; Turnbull, B.W.; Nielsen, Søren Saxmose

2011-01-01

the posterior estimates of the model parameters that provide the basis for inference concerning the accuracy of the diagnostic procedure. Based on the Bayesian approach, the posterior probability distribution of the change-point onset time can be obtained and used as a criterion for infection diagnosis......-point process with a Weibull survival hazard function was used to model the progression of the hidden disease status. The model adjusted for the fixed effects of covariate variables and random effects of subject on the diagnostic testing procedure. Markov chain Monte Carlo methods were used to compute....... An application is presented to an analysis of ELISA and fecal culture test outcomes in the diagnostic testing of paratuberculosis (Johne's disease) for a Danish longitudinal study from January 2000 to March 2003. The posterior probability criterion based on the Bayesian model with 4 repeated observations has...

Creutzfeldt-Jakob disease: updated diagnostic criteria, treatment algorithm, and the utility of brain biopsy.

Science.gov (United States)

Manix, Marc; Kalakoti, Piyush; Henry, Miriam; Thakur, Jai; Menger, Richard; Guthikonda, Bharat; Nanda, Anil

2015-11-01

Creutzfeldt-Jakob disease (CJD) is a rare neurodegenerative condition with a rapid disease course and a mortality rate of 100%. Several forms of the disease have been described, and the most common is the sporadic type. The most challenging aspect of this disease is its diagnosis-the gold standard for definitive diagnosis is considered to be histopathological confirmation-but newer tests are providing means for an antemortem diagnosis in ways less invasive than brain biopsy. Imaging studies, electroencephalography, and biomarkers are used in conjunction with the clinical picture to try to make the diagnosis of CJD without brain tissue samples, and all of these are reviewed in this article. The current diagnostic criteria are limited; test sensitivity and specificity varies with the genetics of the disease as well as the clinical stage. Physicians may be unsure of all diagnostic testing available, and may order outdated tests or prematurely request a brain biopsy when the diagnostic workup is incomplete. The authors review CJD, discuss the role of brain biopsy in this patient population, provide a diagnostic pathway for the patient presenting with rapidly progressive dementia, and propose newer diagnostic criteria.

Evaluation of microscopy and rapid diagnostic tests in screening ...

African Journals Online (AJOL)

Malaria is a life-threatening disease caused by the protozoa of the genus Plasmodium. Infection of individual is through the bites of infected female Anopheles mosquitoes. This study evaluated the performance of microscopy and rapid diagnostic tests (RDTs) in diagnosing malaria. A total of 400 clinically suspected malaria ...

Decision analysis to complete diagnostic research by closing the gap between test characteristics and cost-effectiveness.

Science.gov (United States)

Schaafsma, Joanna D; van der Graaf, Yolanda; Rinkel, Gabriel J E; Buskens, Erik

2009-12-01

The lack of a standard methodology in diagnostic research impedes adequate evaluation before implementation of constantly developing diagnostic techniques. We discuss the methodology of diagnostic research and underscore the relevance of decision analysis in the process of evaluation of diagnostic tests. Overview and conceptual discussion. Diagnostic research requires a stepwise approach comprising assessment of test characteristics followed by evaluation of added value, clinical outcome, and cost-effectiveness. These multiple goals are generally incompatible with a randomized design. Decision-analytic models provide an important alternative through integration of the best available evidence. Thus, critical assessment of clinical value and efficient use of resources can be achieved. Decision-analytic models should be considered part of the standard methodology in diagnostic research. They can serve as a valid alternative to diagnostic randomized clinical trials (RCTs).

Diagnostic Test Accuracy of a 2-Transcript Host RNA Signature for Discriminating Bacterial vs Viral Infection in Febrile Children.

Science.gov (United States)

Herberg, Jethro A; Kaforou, Myrsini; Wright, Victoria J; Shailes, Hannah; Eleftherohorinou, Hariklia; Hoggart, Clive J; Cebey-López, Miriam; Carter, Michael J; Janes, Victoria A; Gormley, Stuart; Shimizu, Chisato; Tremoulet, Adriana H; Barendregt, Anouk M; Salas, Antonio; Kanegaye, John; Pollard, Andrew J; Faust, Saul N; Patel, Sanjay; Kuijpers, Taco; Martinón-Torres, Federico; Burns, Jane C; Coin, Lachlan J M; Levin, Michael

Because clinical features do not reliably distinguish bacterial from viral infection, many children worldwide receive unnecessary antibiotic treatment, while bacterial infection is missed in others. To identify a blood RNA expression signature that distinguishes bacterial from viral infection in febrile children. Febrile children presenting to participating hospitals in the United Kingdom, Spain, the Netherlands, and the United States between 2009-2013 were prospectively recruited, comprising a discovery group and validation group. Each group was classified after microbiological investigation as having definite bacterial infection, definite viral infection, or indeterminate infection. RNA expression signatures distinguishing definite bacterial from viral infection were identified in the discovery group and diagnostic performance assessed in the validation group. Additional validation was undertaken in separate studies of children with meningococcal disease (n = 24) and inflammatory diseases (n = 48) and on published gene expression datasets. A 2-transcript RNA expression signature distinguishing bacterial infection from viral infection was evaluated against clinical and microbiological diagnosis. Definite bacterial and viral infection was confirmed by culture or molecular detection of the pathogens. Performance of the RNA signature was evaluated in the definite bacterial and viral group and in the indeterminate infection group. The discovery group of 240 children (median age, 19 months; 62% male) included 52 with definite bacterial infection, of whom 36 (69%) required intensive care, and 92 with definite viral infection, of whom 32 (35%) required intensive care. Ninety-six children had indeterminate infection. Analysis of RNA expression data identified a 38-transcript signature distinguishing bacterial from viral infection. A smaller (2-transcript) signature (FAM89A and IFI44L) was identified by removing highly correlated transcripts. When this 2-transcript

Lacrimination in Sjogren′s syndrome. Is Schirmer′s test really a useful diagnostic tool?

Directory of Open Access Journals (Sweden)

Bhadoria D

1988-01-01

Full Text Available In the past, Schinier′s test was used as a diagnostic tool in Sjogren′s Syndrome. In this study, a comparison of 100 normal patients with 2l patients with Sjogren′s Syndrome has been made to study its reliability. It has been concluded that Schimer′s test is of a poor diagnostic value in Sjogren′s Syndrome.

Management of SPN in France. Pathways for definitive diagnosis of solitary pulmonary nodule: a multicentre study in 18 French districts

International Nuclear Information System (INIS)

Alzahouri, Kazem; Velten, Michel; Arveux, Patrick; Woronoff-Lemsi, Marie-Christine; Jolly, Damien; Guillemin, Francis

2008-01-01

The process of diagnosis and management of solitary pulmonary nodules (SPNs) between 1 and 3 cm is not standardized. This multicentre study investigated how diagnosis of newly discovered SPNs is managed in routine practice. We examined 11,515 radiology reports of patients undergoing chest computed tomography (CT) at all 76 radiology centres in 18 French administrative districts covering 8,220,000 people. Information on diagnostic procedures and treatment administered from discovery to definitive diagnosis of SPN was collected prospectively. We identified 152 cases of newly diagnosed SPNs. Follow-up was complete for 112 patients. The median number of diagnostic tests was 4 and the mean time to diagnosis was 41.4 days. Marked variability was observed in the sequence of diagnostic tests, and 8 diagnostic pathways were identified. Patients' characteristics and radiological features of SPNs influenced the number of tests performed. Referral by specialist, history of smoking and spiculated SPN predicted the performance of at least one invasive procedure (P < 0.01). Definitive diagnosis was a malignant disease in 30 patients (26%). The diagnosis of SPN is a complex process that physicians approach in markedly different ways. Implementing practice guidelines for managing the diagnosis of SPN requires clarification

DIAGNOSTIC CHARACTERISTICS OF THE COMPUTER TESTS FORMED BY METHOD OF RESTORED FRAGMENTS

Directory of Open Access Journals (Sweden)

Oleksandr O. Petkov

2013-03-01

Full Text Available Definition of validity and reliability of tests which are formed by a method of restored fragments is considered in the article. The structure of the controlled theoretical material of limit field of knowledge, language expressions that describe the subject of control, and reliability of test, is analyzed. The technique of definition of the most important components of reliability of the considered tests is given: reliability of quantitative determination of coefficient of assimilation and technological reliability. Results of the lead pedagogical experiments have proved, that tests of the given class allow to make the control of mastering of a theoretical material over a level of reproduction in any field of knowledge with high reliability. It is shown, that validity tests with restored fragments basically caused by a degree of structurization and methodical study of a controllable material and can achieve beforehand set parameters, down to a level of absolute validity.

Diagnostic Accuracy of Tests for Polyuria in Lithium-Treated Patients.

Science.gov (United States)

Kinahan, James Conor; NiChorcorain, Aoife; Cunningham, Sean; Freyne, Aideen; Cooney, Colm; Barry, Siobhan; Kelly, Brendan D

2015-08-01

In lithium-treated patients, polyuria increases the risk of dehydration and lithium toxicity. If detected early, it is reversible. Despite its prevalence and associated morbidity in clinical practice, it remains underrecognized and therefore undertreated. The 24-hour urine collection is limited by its convenience and practicality. This study explores the diagnostic accuracy of alternative tests such as questionnaires on subjective polyuria, polydipsia, nocturia (dichotomous and ordinal responses), early morning urine sample osmolality (EMUO), and fluid intake record (FIR). This is a cross-sectional study of 179 lithium-treated patients attending a general adult and an old age psychiatry service. Participants completed the tests after completing an accurate 24-hour urine collection. The diagnostic accuracy of the individual tests was explored using the appropriate statistical techniques. Seventy-nine participants completed all of the tests. Polydipsia severity, EMUO, and FIR significantly differentiated the participants with polyuria (area under the receiver operating characteristic curve of 0.646, 0.760, and 0.846, respectively). Of the tests investigated, the FIR made the largest significant change in the probability that a patient experiences polyuria (3500 mL/24 hours; interval likelihood ratio, 14). Symptomatic questioning, EMUO, and an FIR could be used in clinical practice to inform the prescriber of the probability that a lithium-treated patient is experiencing polyuria.

Concordance in diagnostic testing for respiratory pathogens of Bighorn Sheep

Science.gov (United States)

Reliable diagnostic tests are essential for disease investigation and management. This is particularly true for diseases of free-ranging wildlife where sampling is logistically difficult precluding retesting. Clinical assays for wildlife diseases frequently vary among laboratories because of lack ...

Diagnostic Accuracy of the Slump Test for Identifying Neuropathic Pain in the Lower Limb.

Science.gov (United States)

Urban, Lawrence M; MacNeil, Brian J

2015-08-01

Diagnostic accuracy study with nonconsecutive enrollment. To assess the diagnostic accuracy of the slump test for neuropathic pain (NeP) in those with low to moderate levels of chronic low back pain (LBP), and to determine whether accuracy of the slump test improves by adding anatomical or qualitative pain descriptors. Neuropathic pain has been linked with poor outcomes, likely due to inadequate diagnosis, which precludes treatment specific for NeP. Current diagnostic approaches are time consuming or lack accuracy. A convenience sample of 21 individuals with LBP, with or without radiating leg pain, was recruited. A standardized neurosensory examination was used to determine the reference diagnosis for NeP. Afterward, the slump test was administered to all participants. Reports of pain location and quality produced during the slump test were recorded. The neurosensory examination designated 11 of the 21 participants with LBP/sciatica as having NeP. The slump test displayed high sensitivity (0.91), moderate specificity (0.70), a positive likelihood ratio of 3.03, and a negative likelihood ratio of 0.13. Adding the criterion of pain below the knee significantly increased specificity to 1.00 (positive likelihood ratio = 11.9). Pain-quality descriptors did not improve diagnostic accuracy. The slump test was highly sensitive in identifying NeP within the study sample. Adding a pain-location criterion improved specificity. Combining the diagnostic outcomes was very effective in identifying all those without NeP and half of those with NeP. Limitations arising from the small and narrow spectrum of participants with LBP/sciatica sampled within the study prevent application of the findings to a wider population. Diagnosis, level 4-.

Preferred Reporting Items for a Systematic Review and Meta-analysis of Diagnostic Test Accuracy Studies: The PRISMA-DTA Statement.

Science.gov (United States)

McInnes, Matthew D F; Moher, David; Thombs, Brett D; McGrath, Trevor A; Bossuyt, Patrick M; Clifford, Tammy; Cohen, Jérémie F; Deeks, Jonathan J; Gatsonis, Constantine; Hooft, Lotty; Hunt, Harriet A; Hyde, Christopher J; Korevaar, Daniël A; Leeflang, Mariska M G; Macaskill, Petra; Reitsma, Johannes B; Rodin, Rachel; Rutjes, Anne W S; Salameh, Jean-Paul; Stevens, Adrienne; Takwoingi, Yemisi; Tonelli, Marcello; Weeks, Laura; Whiting, Penny; Willis, Brian H

2018-01-23

Systematic reviews of diagnostic test accuracy synthesize data from primary diagnostic studies that have evaluated the accuracy of 1 or more index tests against a reference standard, provide estimates of test performance, allow comparisons of the accuracy of different tests, and facilitate the identification of sources of variability in test accuracy. To develop the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) diagnostic test accuracy guideline as a stand-alone extension of the PRISMA statement. Modifications to the PRISMA statement reflect the specific requirements for reporting of systematic reviews and meta-analyses of diagnostic test accuracy studies and the abstracts for these reviews. Established standards from the Enhancing the Quality and Transparency of Health Research (EQUATOR) Network were followed for the development of the guideline. The original PRISMA statement was used as a framework on which to modify and add items. A group of 24 multidisciplinary experts used a systematic review of articles on existing reporting guidelines and methods, a 3-round Delphi process, a consensus meeting, pilot testing, and iterative refinement to develop the PRISMA diagnostic test accuracy guideline. The final version of the PRISMA diagnostic test accuracy guideline checklist was approved by the group. The systematic review (produced 64 items) and the Delphi process (provided feedback on 7 proposed items; 1 item was later split into 2 items) identified 71 potentially relevant items for consideration. The Delphi process reduced these to 60 items that were discussed at the consensus meeting. Following the meeting, pilot testing and iterative feedback were used to generate the 27-item PRISMA diagnostic test accuracy checklist. To reflect specific or optimal contemporary systematic review methods for diagnostic test accuracy, 8 of the 27 original PRISMA items were left unchanged, 17 were modified, 2 were added, and 2 were omitted. The 27-item

Molecular tools for diagnosis of visceral leishmaniasis: systematic review and meta-analysis of diagnostic test accuracy.

Science.gov (United States)

de Ruiter, C M; van der Veer, C; Leeflang, M M G; Deborggraeve, S; Lucas, C; Adams, E R

2014-09-01

Molecular methods have been proposed as highly sensitive tools for the detection of Leishmania parasites in visceral leishmaniasis (VL) patients. Here, we evaluate the diagnostic accuracy of these tools in a meta-analysis of the published literature. The selection criteria were original studies that evaluate the sensitivities and specificities of molecular tests for diagnosis of VL, adequate classification of study participants, and the absolute numbers of true positives and negatives derivable from the data presented. Forty studies met the selection criteria, including PCR, real-time PCR, nucleic acid sequence-based amplification (NASBA), and loop-mediated isothermal amplification (LAMP). The sensitivities of the individual studies ranged from 29 to 100%, and the specificities ranged from 25 to 100%. The pooled sensitivity of PCR in whole blood was 93.1% (95% confidence interval [CI], 90.0 to 95.2), and the specificity was 95.6% (95% CI, 87.0 to 98.6). The specificity was significantly lower in consecutive studies, at 63.3% (95% CI, 53.9 to 71.8), due either to true-positive patients not being identified by parasitological methods or to the number of asymptomatic carriers in areas of endemicity. PCR for patients with HIV-VL coinfection showed high diagnostic accuracy in buffy coat and bone marrow, ranging from 93.1 to 96.9%. Molecular tools are highly sensitive assays for Leishmania detection and may contribute as an additional test in the algorithm, together with a clear clinical case definition. We observed wide variety in reference standards and study designs and now recommend consecutively designed studies. Copyright © 2014, American Society for Microbiology. All Rights Reserved.

Plasma diagnostic development and UHV testing for the ALPHA collaboration at Marquette University

Science.gov (United States)

Tharp, T. D.; Alpha Collaboration

2017-10-01

At Marquette, we are developing the next generation of nonneutral plasma diagnostics for the ALPHA experiment at CERN. ALPHA is building a new vertical experiment to test the gravitational interaction of antihydrogen with Earth. This expansion requires significant changes to the design of our plasma diagnostic suites: the next generation of tools must be able to measure plasmas from two directions, and must be capable of operating in a horizontal position. The diagnostic suite includes measurements of plasma density, shape, and temperature. The hardware used includes a MicroChannel Plate (MCP), a Faraday Cup, and an electron gun. In addition, we are building a vacuum chamber to test the viability of 3-d printed components for UHV compatibility, with target pressures of 10-10 mbar.

Validation of clinical case definition of acute intussusception in infants in Viet Nam and Australia.

OpenAIRE

Bines, JE; Liem, NT; Justice, F; Son, TN; Carlin, JB; de Campo, M; Jamsen, K; Mulholland, K; Barnett, P; Barnes, GL

2006-01-01

OBJECTIVE: To test the sensitivity and specificity of a clinical case definition of acute intussusception in infants to assist health-care workers in settings where diagnostic facilities are not available. METHODS: Prospective studies were conducted at a major paediatric hospital in Viet Nam (the National Hospital of Pediatrics, Hanoi) from November 2002 to December 2003 and in Australia (the Royal Children's Hospital, Melbourne) from March 2002 to March 2004 using a clinical case definition ...

Classification of chronic orofacial pain using an intravenous diagnostic test

NARCIS (Netherlands)

Tjakkes, G. -H. E.; De Bont, L. G. M.; van Wijhe, M.; Stegenga, B.

The aim of this study was to evaluate the ability of a preliminary intravenous diagnostic test to classify chronic orofacial pain patients into different subgroups. Patients with chronic orofacial pain conditions that could not be unambiguously diagnosed. A retrospective evaluation of series of

Portuguese Family Physicians' Awareness of Diagnostic and Laboratory Test Costs: A Cross-Sectional Study.

Directory of Open Access Journals (Sweden)

Luísa Sá

Full Text Available Physicians' ability to make cost-effective decisions has been shown to be affected by their knowledge of health care costs. This study assessed whether Portuguese family physicians are aware of the costs of the most frequently prescribed diagnostic and laboratory tests.A cross-sectional study was conducted in a representative sample of Portuguese family physicians, using computer-assisted telephone interviews for data collection. A Likert scale was used to assess physician's level of agreement with four statements about health care costs. Family physicians were also asked to estimate the costs of diagnostic and laboratory tests. Each physician's cost estimate was compared with the true cost and the absolute error was calculated.One-quarter (24%; 95% confidence interval: 23%-25% of all cost estimates were accurate to within 25% of the true cost, with 55% (95% IC: 53-56 overestimating and 21% (95% IC: 20-22 underestimating the true actual cost. The majority (76% of family physicians thought they did not have or were uncertain as to whether they had adequate knowledge of diagnostic and laboratory test costs, and only 7% reported receiving adequate education. The majority of the family physicians (82% said that they had adequate access to information about the diagnostic and laboratory test costs. Thirty-three percent thought that costs did not influence their decision to order tests, while 27% were uncertain.Portuguese family physicians have limited awareness of diagnostic and laboratory test costs, and our results demonstrate a need for improved education in this area. Further research should focus on identifying whether interventions in cost knowledge actually change ordering behavior, in identifying optimal methods to disseminate cost information, and on improving the cost-effectiveness of care.

Portuguese Family Physicians’ Awareness of Diagnostic and Laboratory Test Costs: A Cross-Sectional Study

Science.gov (United States)

Sá, Luísa; Costa-Santos, Cristina; Teixeira, Andreia; Couto, Luciana; Costa-Pereira, Altamiro; Hespanhol, Alberto; Santos, Paulo; Martins, Carlos

2015-01-01

Background Physicians’ ability to make cost-effective decisions has been shown to be affected by their knowledge of health care costs. This study assessed whether Portuguese family physicians are aware of the costs of the most frequently prescribed diagnostic and laboratory tests. Methods A cross-sectional study was conducted in a representative sample of Portuguese family physicians, using computer-assisted telephone interviews for data collection. A Likert scale was used to assess physician’s level of agreement with four statements about health care costs. Family physicians were also asked to estimate the costs of diagnostic and laboratory tests. Each physician’s cost estimate was compared with the true cost and the absolute error was calculated. Results One-quarter (24%; 95% confidence interval: 23%–25%) of all cost estimates were accurate to within 25% of the true cost, with 55% (95% IC: 53–56) overestimating and 21% (95% IC: 20–22) underestimating the true actual cost. The majority (76%) of family physicians thought they did not have or were uncertain as to whether they had adequate knowledge of diagnostic and laboratory test costs, and only 7% reported receiving adequate education. The majority of the family physicians (82%) said that they had adequate access to information about the diagnostic and laboratory test costs. Thirty-three percent thought that costs did not influence their decision to order tests, while 27% were uncertain. Conclusions Portuguese family physicians have limited awareness of diagnostic and laboratory test costs, and our results demonstrate a need for improved education in this area. Further research should focus on identifying whether interventions in cost knowledge actually change ordering behavior, in identifying optimal methods to disseminate cost information, and on improving the cost-effectiveness of care. PMID:26356625

Dual Processing Model for Medical Decision-Making: An Extension to Diagnostic Testing.

Science.gov (United States)

Tsalatsanis, Athanasios; Hozo, Iztok; Kumar, Ambuj; Djulbegovic, Benjamin

2015-01-01

Dual Processing Theories (DPT) assume that human cognition is governed by two distinct types of processes typically referred to as type 1 (intuitive) and type 2 (deliberative). Based on DPT we have derived a Dual Processing Model (DPM) to describe and explain therapeutic medical decision-making. The DPM model indicates that doctors decide to treat when treatment benefits outweigh its harms, which occurs when the probability of the disease is greater than the so called "threshold probability" at which treatment benefits are equal to treatment harms. Here we extend our work to include a wider class of decision problems that involve diagnostic testing. We illustrate applicability of the proposed model in a typical clinical scenario considering the management of a patient with prostate cancer. To that end, we calculate and compare two types of decision-thresholds: one that adheres to expected utility theory (EUT) and the second according to DPM. Our results showed that the decisions to administer a diagnostic test could be better explained using the DPM threshold. This is because such decisions depend on objective evidence of test/treatment benefits and harms as well as type 1 cognition of benefits and harms, which are not considered under EUT. Given that type 1 processes are unique to each decision-maker, this means that the DPM threshold will vary among different individuals. We also showed that when type 1 processes exclusively dominate decisions, ordering a diagnostic test does not affect a decision; the decision is based on the assessment of benefits and harms of treatment. These findings could explain variations in the treatment and diagnostic patterns documented in today's clinical practice.

Dual Processing Model for Medical Decision-Making: An Extension to Diagnostic Testing.

Directory of Open Access Journals (Sweden)

Athanasios Tsalatsanis

Full Text Available Dual Processing Theories (DPT assume that human cognition is governed by two distinct types of processes typically referred to as type 1 (intuitive and type 2 (deliberative. Based on DPT we have derived a Dual Processing Model (DPM to describe and explain therapeutic medical decision-making. The DPM model indicates that doctors decide to treat when treatment benefits outweigh its harms, which occurs when the probability of the disease is greater than the so called "threshold probability" at which treatment benefits are equal to treatment harms. Here we extend our work to include a wider class of decision problems that involve diagnostic testing. We illustrate applicability of the proposed model in a typical clinical scenario considering the management of a patient with prostate cancer. To that end, we calculate and compare two types of decision-thresholds: one that adheres to expected utility theory (EUT and the second according to DPM. Our results showed that the decisions to administer a diagnostic test could be better explained using the DPM threshold. This is because such decisions depend on objective evidence of test/treatment benefits and harms as well as type 1 cognition of benefits and harms, which are not considered under EUT. Given that type 1 processes are unique to each decision-maker, this means that the DPM threshold will vary among different individuals. We also showed that when type 1 processes exclusively dominate decisions, ordering a diagnostic test does not affect a decision; the decision is based on the assessment of benefits and harms of treatment. These findings could explain variations in the treatment and diagnostic patterns documented in today's clinical practice.

Development, Evaluation, and Integration of a Quantitative Reverse-Transcription Polymerase Chain Reaction Diagnostic Test for Ebola Virus on a Molecular Diagnostics Platform.

Science.gov (United States)

Cnops, Lieselotte; Van den Eede, Peter; Pettitt, James; Heyndrickx, Leo; De Smet, Birgit; Coppens, Sandra; Andries, Ilse; Pattery, Theresa; Van Hove, Luc; Meersseman, Geert; Van Den Herrewegen, Sari; Vergauwe, Nicolas; Thijs, Rein; Jahrling, Peter B; Nauwelaers, David; Ariën, Kevin K

2016-10-15

 The 2013-2016 Ebola epidemic in West Africa resulted in accelerated development of rapid diagnostic tests for emergency outbreak preparedness. We describe the development and evaluation of the Idylla™ prototype Ebola virus test, a fully automated sample-to-result molecular diagnostic test for rapid detection of Zaire ebolavirus (EBOV) and Sudan ebolavirus (SUDV).  The Idylla™ prototype Ebola virus test can simultaneously detect EBOV and SUDV in 200 µL of whole blood. The sample is directly added to a disposable cartridge containing all reagents for sample preparation, RNA extraction, and amplification by reverse-transcription polymerase chain reaction analysis. The performance was evaluated with a variety of sample types, including synthetic constructs and whole blood samples from healthy volunteers spiked with viral RNA, inactivated virus, and infectious virus.  The 95% limits of detection for EBOV and SUDV were 465 plaque-forming units (PFU)/mL (1010 copies/mL) and 324 PFU/mL (8204 copies/mL), respectively. In silico and in vitro analyses demonstrated 100% correct reactivity for EBOV and SUDV and no cross-reactivity with relevant pathogens. The diagnostic sensitivity was 97.4% (for EBOV) and 91.7% (for SUDV), the specificity was 100%, and the diagnostic accuracy was 95.9%.  The Idylla™ prototype Ebola virus test is a fast, safe, easy-to-use, and near-patient test that meets the performance criteria to detect EBOV in patients with suspected Ebola. © The Author 2016. Published by Oxford University Press for the Infectious Diseases Society of America. All rights reserved. For permissions, e-mail journals.permissions@oup.com.

Blood culture-negative endocarditis: Improving the diagnostic yield using new diagnostic tools.

Science.gov (United States)

Fournier, Pierre-Edouard; Gouriet, Frédérique; Casalta, Jean-Paul; Lepidi, Hubert; Chaudet, Hervé; Thuny, Franck; Collart, Frédéric; Habib, Gilbert; Raoult, Didier

2017-11-01

Blood culture-negative endocarditis (BCNE) may represent up to 70% of all endocarditis cases, depending on series. From 2001 to 2009, we implemented in our laboratory a multimodal diagnostic strategy for BCNE that included systematized testing of blood, and when available, valvular biopsy specimens using serological, broad range molecular, and histopathological assays. A causative microorganism was identified in 62.7% of patients.In this study from January 2010 to December 2015, in an effort to increase the number of identified causative microorganisms, we prospectively added to our diagnostic protocol specific real-time (RT) polymerase chain reaction (PCR) assays targeting various endocarditis agents, and applied them to all patients with BCNE admitted to the 4 public hospitals in Marseille, France.A total of 283 patients with BCNE were included in the study. Of these, 177 were classified as having definite endocarditis. Using our new multimodal diagnostic strategy, we identified an etiology in 138 patients (78.0% of cases). Of these, 3 were not infective (2.2%) and 1 was diagnosed as having Mycobacterium bovis BCG endocarditis. By adding specific PCR assays from blood and valvular biopsies, which exhibited a significantly greater sensitivity (P < 10) than other methods, causative agents, mostly enterococci, streptococci, and zoonotic microorganisms, were identified in an additional 27 patients (14 from valves only, 11 from blood only, and 2 from both). Finally, in another 107 patients, a pathogen was detected using serology in 37, valve culture in 8, broad spectrum PCR from valvular biopsies and blood in 19 and 2, respectively, immunohistochemistry from valves in 3, and a combination of several assays in 38.By adding specific RT-PCR assays to our systematic PCR testing of patients with BCNE, we increased the diagnostic efficiency by 24.3%, mostly by detecting enterococci and streptococci that had not been detected by other diagnostic methods, but also agents

In Search of Optimal Cognitive Diagnostic Model(s) for ESL Grammar Test Data

Science.gov (United States)

Yi, Yeon-Sook

2017-01-01

This study compares five cognitive diagnostic models in search of optimal one(s) for English as a Second Language grammar test data. Using a unified modeling framework that can represent specific models with proper constraints, the article first fit the full model (the log-linear cognitive diagnostic model, LCDM) and investigated which model…

Consensus-based reporting standards for diagnostic test accuracy studies for paratuberculosis in ruminants

DEFF Research Database (Denmark)

Gardner, Ian A.; Nielsen, Søren Saxmose; Whittington, Richard

2011-01-01

The Standards for Reporting of Diagnostic Accuracy (STARD) statement (www.stard-statement.org) was developed to encourage complete and transparent reporting of key elements of test accuracy studies in human medicine. The statement was motivated by widespread evidence of bias in test accuracy...... studies and the finding that incomplete or absent reporting of items in the STARD checklist was associated with overly optimistic estimates of test performance characteristics. Although STARD principles apply broadly, specific guidelines do not exist to account for unique considerations in livestock...... for Reporting of Animal Diagnostic Accuracy Studies for paratuberculosis), should facilitate improved quality of reporting of the design, conduct and results of paratuberculosis test accuracy studies which were identified as “poor” in a review published in 2008 in Veterinary Microbiology...

Muscular Dystrophy Surveillance Tracking and Research Network (MD STARnet): case definition in surveillance for childhood-onset Duchenne/Becker muscular dystrophy.

Science.gov (United States)

Mathews, Katherine D; Cunniff, Chris; Kantamneni, Jiji R; Ciafaloni, Emma; Miller, Timothy; Matthews, Dennis; Cwik, Valerie; Druschel, Charlotte; Miller, Lisa; Meaney, F John; Sladky, John; Romitti, Paul A

2010-09-01

The Muscular Dystrophy Surveillance Tracking and Research Network (MD STARnet) is a multisite collaboration to determine the prevalence of childhood-onset Duchenne/Becker muscular dystrophy and to characterize health care and health outcomes in this population. MD STARnet uses medical record abstraction to identify patients with Duchenne/Becker muscular dystrophy born January 1, 1982 or later who resided in 1 of the participating sites. Critical diagnostic elements of each abstracted record are reviewed independently by >4 clinicians and assigned to 1 of 6 case definition categories (definite, probable, possible, asymptomatic, female, not Duchenne/Becker muscular dystrophy) by consensus. As of November 2009, 815 potential cases were reviewed. Of the cases included in analysis, 674 (82%) were either ''definite'' or ''probable'' Duchenne/Becker muscular dystrophy. These data reflect a change in diagnostic testing, as case assignment based on genetic testing increased from 67% in the oldest cohort (born 1982-1987) to 94% in the cohort born 2004 to 2009.

Convergent and diagnostic validity of STAVUX, a word and pseudoword spelling test for adults.

Science.gov (United States)

Östberg, Per; Backlund, Charlotte; Lindström, Emma

2016-10-01

Few comprehensive spelling tests are available in Swedish, and none have been validated in adults with reading and writing disorders. The recently developed STAVUX test includes word and pseudoword spelling subtests with high internal consistency and adult norms stratified by education. This study evaluated the convergent and diagnostic validity of STAVUX in adults with dyslexia. Forty-six adults, 23 with dyslexia and 23 controls, took STAVUX together with a standard word-decoding test and a self-rated measure of spelling skills. STAVUX subtest scores showed moderate to strong correlations with word-decoding scores and predicted self-rated spelling skills. Word and pseudoword subtest scores both predicted dyslexia status. Receiver-operating characteristic (ROC) analysis showed excellent diagnostic discriminability. Sensitivity was 91% and specificity 96%. In conclusion, the results of this study support the convergent and diagnostic validity of STAVUX.

A new condition for assessing the clinical efficiency of a diagnostic test.

Science.gov (United States)

Bokhari, Ehsan; Hubert, Lawrence

2015-09-01

When prediction using a diagnostic test outperforms simple prediction using base rates, the test is said to be "clinically efficient," a term first introduced into the literature by Meehl and Rosen (1955) in Psychological Bulletin. This article provides three equivalent conditions for determining the clinical efficiency of a diagnostic test: (a) Meehl-Rosen (Meehl & Rosen, 1955); (b) Dawes (Dawes, 1962); and (c) the Bokhari-Hubert condition, introduced here for the first time. Clinical efficiency is then generalized to situations where misclassification costs are considered unequal (for example, false negatives are more costly than false positives). As an illustration, the clinical efficiency of an actuarial device for predicting violent and dangerous behavior is examined that was developed as part of the MacArthur Violence Risk Assessment Study. (c) 2015 APA, all rights reserved.

Diagnostics of trophoblast disease and the control of therapeutic efficiency based on definition of chorionic gonadotrapin and trophoblastic beta1-glycoprotein

International Nuclear Information System (INIS)

Yugrinova, L.G.; Olefirenko, G.A.; Dotsenko, Yu.S.

1982-01-01

A comparative estimation of markers of trophoblast disease, chorionic gonadotropin (CG) and trophoblastic beta 1 -glycoprotein defined by different methods is given. It is found that diagnostics and control of therapeutic efficiency for patients having trophoblast disease based on CG definition are possible. In 86% of cases the clinical diagnosis was confirmed by the immunoradioautography, and in 33% - by the immunodiffusion method. The dependence of marker detection frequency on the therapeutic efficiency is found

Quality assurance in diagnostic radiology in Hungary - first experiences in acceptance testing

International Nuclear Information System (INIS)

Porubszky, T.; Pellet, S.; Ballay, L.; Talian, L.; Giczi, F.

2003-01-01

It is a general experience that optimum imaging with minimum patient doses, moreover, the safe operation and long life of X-ray equipment can be assured by regular measurement of technical parameters and checking of their constancy (routine performance testing) only. These tests are generally known as quality control, while together with the so-called corrective actions and its management it is called (physical-technical) quality assurance (QA). In the European Union, Directive 97/43/EURATOM about radiation protection of patients requires - among others - the good practice of (physical-technical) quality assurance. In Hungary, Decree No. 31/2001. (X.3.) of the Minister of Health harmonizes all of its requirements. Acceptance testing of new diagnostic X-ray equipment is assigned to NPHC-NRIRR. QA has been a daily practice in radiation therapy and nuclear medicine for a long time. A National Patient Dose Assessment Programme has also successfully run since 1989. We had, however, only few preliminaries in QA in diagnostic radiology in the second half of the eighties. Nowadays there are running QA programmes in some hospitals and mammography centres. he testing activity of our institute is independent from manufacturers, it is run within the frame of an accredited testing laboratory, using calibrated measuring instruments and based on valid international standards. So the started way of implementing QA in diagnostic radiology needs a lot of further efforts, adapting experiences of other countries, and also some financial help to reach an acceptable level in the EU. (authors)

Accuracy of clinical diagnosis versus the World Health Organization case definition in the Amoy Garden SARS cohort.

Science.gov (United States)

Wong, W N; Sek, Antonio C H; Lau, Rick F L; Li, K M; Leung, Joe K S; Tse, M L; Ng, Andy H W; Stenstrom, Robert

2003-11-01

To compare the diagnostic accuracy of emergency department (ED) physicians with the World Health Organization (WHO) case definition in a large community-based SARS (severe acute respiratory syndrome) cohort. This was a cohort study of all patients from Hong Kong's Amoy Garden complex who presented to an ED SARS screening clinic during a 2-month outbreak. Clinical findings and WHO case definition criteria were recorded, along with ED diagnoses. Final diagnoses were established independently based on relevant diagnostic tests performed after the ED visit. Emergency physician diagnostic accuracy was compared with that of the WHO SARS case definition. Sensitivity, specificity, predictive values and likelihood ratios were calculated using standard formulae. During the study period, 818 patients presented with SARS-like symptoms, including 205 confirmed SARS, 35 undetermined SARS and 578 non-SARS. Sensitivity, specificity and accuracy were 91%, 96% and 94% for ED clinical diagnosis, versus 42%, 86% and 75% for the WHO case definition. Positive likelihood ratios (LR+) were 21.1 for physician judgement and 3.1 for the WHO criteria. Negative likelihood ratios (LR-) were 0.10 for physician judgement and 0.67 for the WHO criteria, indicating that clinician judgement was a much more powerful predictor than the WHO criteria. Physician clinical judgement was more accurate than the WHO case definition. Reliance on the WHO case definition as a SARS screening tool may lead to an unacceptable rate of misdiagnosis. The SARS case definition must be revised if it is to be used as a screening tool in emergency departments and primary care settings.

Syphilis and neurosyphilis: HIV-coinfection and value of diagnostic parameters in cerebrospinal fluid.

Science.gov (United States)

Merins, V; Hahn, K

2015-10-07

Neurosyphilis might be difficult to diagnose particularly in asymptomatic patients and patients with HIV-coinfection. The objective of this study was to evaluate current diagnostic standards for neurosyphilis in HIV-positive and -negative patients. We studied retrospectively patients with an active syphilis infection who had additionally undergone lumbar puncture. Patients where the criteria for the diagnosis of a definite or probable neurosyphilis were applicable were further analyzed for clinical symptoms, CSF, HIV-status as well as Treponema pallidum testing in serum and CSF. Correlation analysis of categorical variables was done by using the Chi-square test or in cases of small sample sizes the exact test of Fisher. p values ≤0.05 were considered significant. Eighty-nine patients were diagnosed with syphilis. All necessary criteria for the diagnosis of a neurosyphilis were available in 67 of them including 35 HIV-positive and 32 HIV-negative patients. A definite neurosyphilis could be retrospectively diagnosed in 13 and a probable in another 25 cases. Normal CSF results were more likely in HIV-negatives (p = 0.016). A neurosyphilis was correlated to a CSF pleocytosis > 5 cells/µl and to an albumin quotient >7.8 mg/dl regardless of a parallel HIV infection. HIV-positives had more frequently a CSF-RPR titre >1:4 than HIV-negatives (p = 0.031). However, the RPR test in CSF in definite or probable neurosyphilis had a sensitivity of only 21 %. Our data show that a pleocytosis and an elevated albumin quotient correlate with neurosyphilis. However, the CSF-RPR test as gold standard in neurosyphilis diagnostics has a very low sensitivity.

2012 HIV Diagnostics Conference: the molecular diagnostics perspective.

Science.gov (United States)

Branson, Bernard M; Pandori, Mark

2013-04-01

2012 HIV Diagnostic Conference Atlanta, GA, USA, 12-14 December 2012. This report highlights the presentations and discussions from the 2012 National HIV Diagnostic Conference held in Atlanta (GA, USA), on 12-14 December 2012. Reflecting changes in the evolving field of HIV diagnostics, the conference provided a forum for evaluating developments in molecular diagnostics and their role in HIV diagnosis. In 2010, the HIV Diagnostics Conference concluded with the proposal of a new diagnostic algorithm which included nucleic acid testing to resolve discordant screening and supplemental antibody test results. The 2012 meeting, picking up where the 2010 meeting left off, focused on scientific presentations that assessed this new algorithm and the role played by RNA testing and new developments in molecular diagnostics, including detection of total and integrated HIV-1 DNA, detection and quantification of HIV-2 RNA, and rapid formats for detection of HIV-1 RNA.

Culture-independent diagnostic testing: have we opened Pandora's box for good?

Science.gov (United States)

Janda, J Michael; Abbott, Sharon A

2014-11-01

The ability to accurately and quickly identify microbial agents associated with infectious diseases has been a longstanding and continuous goal of diagnostic microbiology laboratories. Over the course of several decades, technology and testing methodologies in this field have gradually evolved from traditional- or classic-based culture and identification approaches to antigen capture systems and more molecular-oriented applications. Recently, these molecular-based applications have signaled a new era in clinical diagnostic microbiology with the commercial introduction of culture-independent diagnostic testing (CIDT) systems. The first major commercial venture into the CIDT arena involves the detection of acute bacterial gastroenteritis. Several commercial products are now on the market globally with at least 4 Food and Drug Administration approved since January of 2013. These new systems offer the direct detection of a variety of enteropathogens quickly without the need for traditional culture. In Greek mythology, Pandora opened a "jar" or "box" out of curiosity thereby releasing all of humanity's evils most notably diseases and plagues according to Hesiod's Theogony. While not ill-intentioned the only thing left in the box was Hope. Copyright © 2014 Elsevier Inc. All rights reserved.

Usage of Latent Class Analysis in Diagnostic Microbiology in the Absence of Gold Standard Test

Directory of Open Access Journals (Sweden)

Gul Bayram Abiha

2016-12-01

Full Text Available The evaluation of performance of various tests diagnostic tests in the absence of gold standard is an important problem. Latent class analysis (LCA is a statistical analysis method known for many years, especially in the absence of a gold standard for evaluation of diagnostic tests so that LCA has found its wide application area. During the last decade, LCA method has widely used in for determining sensivity and specifity of different microbiological tests. It has investigated in the diagnosis of mycobacterium tuberculosis, mycobacterium bovis, human papilloma virus, bordetella pertussis, influenza viruses, hepatitis E virus (HEV, hepatitis C virus (HCV and other various viral infections. Researchers have compared several diagnostic tests for the diagnosis of different pathogens with LCA. We aimed to evaluate performance of latent class analysis method used microbiological diagnosis in various diseases in several researches. When we took into account all of these tests' results, we suppose that LCA is a good statistical analysis method to assess different test performances in the absence of gold standard. [Archives Medical Review Journal 2016; 25(4.000: 467-488

Laboratory evaluation of immunochromatographic rapid diagnostic tests for cholera in Haiti.

Directory of Open Access Journals (Sweden)

Wilfredo R Matias

Full Text Available Rapid diagnostic tests (RDT for cholera are promising tools for detecting cholera in areas with limited laboratory infrastructure. However, evidence on the characteristics of the many available RDTs is scarce, and their use has been limited by suboptimal performance. We evaluated the performance characteristics of three cholera RDTs from Span Diagnostics, Artron Laboratories, and Standard Diagnostics in a regional laboratory in Haiti.We retrospectively reviewed records from May 2014 to October 2015 of a laboratory-based surveillance program for Vibrio cholerae at Hôpital Saint-Nicolas in Saint-Marc, Haiti. We compared the results of 511 Crystal VC, 129 Artron and 451 SD Bioline RDTs to bacterial culture as the gold standard. Of 905 cultures, 477 (52.7% were positive for V. cholerae O1, of which 27.7% were serotype Inaba. No cultures grew V. cholerae O139. Sensitivity and specificity of Crystal VC were 98.6% (95%CI: 96.5%-99.6% and 71.1% (95%CI: 64.7%-76.9%, respectively. Artron demonstrated a sensitivity of 98.6% (95%CI: 92.7%-100% and specificity of 69.1% (95%CI: 55.2%-80.9%. SD Bioline demonstrated a sensitivity of 81.1% (95%CI: 75.6%-85.8% and specificity of 92.8% (95%CI: 88.4%-95.9%. Crystal VC and Artron frequently showed false positive O139 bands, whereas none were seen with SD Bioline.There is significant variation in the performance of different cholera diagnostic RDTs. Artron and Crystal VC RDTs have high sensitivity and low specificity, while SD Bioline RDT has low to moderate sensitivity and high specificity when performed by laboratory technicians in Haiti. Study limitations included its retrospective design. The suboptimal characteristics of these tests limit their use as clinical point-of-care tests; however, they may be useful in outbreak response, surveillance, and research in resource-limited settings.

Diagnostic accuracy of patch test in children with food allergy.

Science.gov (United States)

Caglayan Sozmen, Sule; Povesi Dascola, Carlotta; Gioia, Edoardo; Mastrorilli, Carla; Rizzuti, Laura; Caffarelli, Carlo

2015-08-01

The gold standard test for confirming whether a child has clinical hypersensitivity reactions to foods is the oral food challenge. Therefore, there is increasing interest in simpler diagnostic markers of food allergy, especially in children, to avoid oral food challenge. The goal of this study was to assess the diagnostic accuracy of atopy patch test in comparison with oral food challenge. We investigated 243 children (mean age, 51 months) referred for evaluation of suspected egg or cow's milk allergy. Skin prick test and atopy patch test were carried out, and after a 2 weeks elimination diet, oral food challenge was performed. Two hundred and forty-three children underwent OFC to the suspected food. We found clinically relevant food allergies in 40 (65%) children to egg and in 22 (35%) to cow's milk. The sensitivity of skin prick test for both milk and egg was 92%, specificity 91%, positive predictive value 35%, and negative predictive value of 93%. Sensitivity, specificity, positive predictive value, and negative predictive value of atopy patch test for both milk and egg were 21%, 73%, 20%, and 74%, respectively. Our study suggests that there is insufficient evidence for the routine use of atopy patch test for the evaluation of egg and cow's milk allergy. OFC remains gold standard for the diagnosis of egg and milk allergy even in the presence of high costs in terms of both time and risks during application. © 2015 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

A compliance testing program for diagnostic X-ray equipment

International Nuclear Information System (INIS)

Hutchinson, D.E.; Cobb, B.J.; Jacob, C.S.

1999-01-01

Compliance testing is nominally that part of a quality assurance program dealing with those aspects of X-ray equipment performance that are subject to radiation control legislation. Quality assurance programs for medical X-ray equipment should be an integral part of the quality culture in health care. However while major hospitals and individual medical centers may implement such programs with some diligence, much X-ray equipment can remain unappraised unless there is a comprehensive regulatory inspection program or some form of compulsion on the equipment owner to implement a testing program. Since the late 1950s all X-ray equipment in the State of Western Australia has been inspected by authorized officers acting on behalf of the Radiological Council, the regulatory authority responsible for administration of the State's Radiation Safety Act. However, economic constraints, coupled with increasing X-ray equipment numbers and a geographically large State have significantly affected the inspection rate. Data available from inspections demonstrate that regular compliance and performance checks are essential in order to ensure proper performance and to minimize unnecessary patient and operator dose. To ensure that diagnostic X-ray equipment complies with accepted standards and performance criteria, the regulatory authority introduced a compulsory compliance testing program for all medical, dental and chiropractic diagnostic X-ray equipment effective from 1 January 1997

78 FR 60898 - Regulation on Definition and Requirements for a Nationally Recognized Testing Laboratory...

Science.gov (United States)

2013-10-02

...] Regulation on Definition and Requirements for a Nationally Recognized Testing Laboratory; Revision of the Office of Management and Budget's (OMB) Approval of Information Collection (Paperwork) Requirements... collection requirements specified by its Regulation at 29 CFR 1910.7, ``definition and requirements for a...

Comparative analysis of two rapid diagnostic tests for diagnosis of ...

African Journals Online (AJOL)

This study aims at comparing the diagnostic efficiencies of two commercially available kits for detecting Plasmodium falciparum infection in urine and blood of febrile patients for malaria diagnosis. This was an observational study in which matched blood and urine from symptomatic patients were tested for malaria using two ...

An audit of diagnostic tests performed in medical microbiology, and ...

African Journals Online (AJOL)

Clinical audit is an important tool for reviewing and improving the quality of service in clinical laboratories. This is a three year audit of diagnostic test carried out in Medical Microbiology and Immunology laboratories of University of Maiduguri Teaching Hospital, Maiduguri, Nigeria. The objectives were to document and ...

Blood tests and prognosis in bladder carcinomas treated with definitive radiotherapy

International Nuclear Information System (INIS)

Hannisdal, E.; Fossa, S.D.; Host, H.

1993-01-01

The value of some commonly recorded blood tests as prognostic factors in patients with bladder carcinomas treated with definitive radiotherapy has been assessed. This study included 202 consecutive patients (T2, n=46; T3, n=82 and T4, n=74) treated during the period 1980-1987. The median total dose received was 56 Gy [50-67] and the median cumulative radiation effect was 1750 reu (radiation effect unit) (1515-1823). The blood tests examined in survival analyses were erythrocyte sedimentation rate (ESR), hemoglobin (Hb), leucocyte and thrombocyte count, alkaline phosphatase (ALP), γ-glutamyltransferase (GT), lactate dehydrogenase (LD), creatinine and albumin. In the univariate survival analyses six blood tests were significant prognostic factors (ESR, albumin, creatinine, Hb, ALP and GT). In the multivariate analysis of all 202 patients, the following five variables were significantly associated with shorter survival: T4 tumors, ESR > 30 mm/h, albumin 400 U/I and age >75 years. Our conclusion is that several commonly recorded blood tests are powerful prognostic factors in bladder cancer treated with definitive radiotherapy. These tests can replace other more expensive laboratory investigations used for prognostication. (author). figs. tabs

42 CFR 440.130 - Diagnostic, screening, preventive, and rehabilitative services.

Science.gov (United States)

2010-10-01

... 42 Public Health 4 2010-10-01 2010-10-01 false Diagnostic, screening, preventive, and rehabilitative services. 440.130 Section 440.130 Public Health CENTERS FOR MEDICARE & MEDICAID SERVICES... Definitions § 440.130 Diagnostic, screening, preventive, and rehabilitative services. (a) “Diagnostic services...

On the Estimation of Disease Prevalence by Latent Class Models for Screening Studies Using Two Screening Tests with Categorical Disease Status Verified in Test Positives Only

Science.gov (United States)

Chu, Haitao; Zhou, Yijie; Cole, Stephen R.; Ibrahim, Joseph G.

2010-01-01

Summary To evaluate the probabilities of a disease state, ideally all subjects in a study should be diagnosed by a definitive diagnostic or gold standard test. However, since definitive diagnostic tests are often invasive and expensive, it is generally unethical to apply them to subjects whose screening tests are negative. In this article, we consider latent class models for screening studies with two imperfect binary diagnostic tests and a definitive categorical disease status measured only for those with at least one positive screening test. Specifically, we discuss a conditional independent and three homogeneous conditional dependent latent class models and assess the impact of misspecification of the dependence structure on the estimation of disease category probabilities using frequentist and Bayesian approaches. Interestingly, the three homogeneous dependent models can provide identical goodness-of-fit but substantively different estimates for a given study. However, the parametric form of the assumed dependence structure itself is not “testable” from the data, and thus the dependence structure modeling considered here can only be viewed as a sensitivity analysis concerning a more complicated non-identifiable model potentially involving heterogeneous dependence structure. Furthermore, we discuss Bayesian model averaging together with its limitations as an alternative way to partially address this particularly challenging problem. The methods are applied to two cancer screening studies, and simulations are conducted to evaluate the performance of these methods. In summary, further research is needed to reduce the impact of model misspecification on the estimation of disease prevalence in such settings. PMID:20191614

Using Meta-Analysis to Inform the Design of Subsequent Studies of Diagnostic Test Accuracy

Science.gov (United States)

Hinchliffe, Sally R.; Crowther, Michael J.; Phillips, Robert S.; Sutton, Alex J.

2013-01-01

An individual diagnostic accuracy study rarely provides enough information to make conclusive recommendations about the accuracy of a diagnostic test; particularly when the study is small. Meta-analysis methods provide a way of combining information from multiple studies, reducing uncertainty in the result and hopefully providing substantial…

Investigation and diagnostic formulation in patients admitted with transient loss of consciousness

LENUS (Irish Health Repository)

Briggs, R

2017-05-01

Several commonly completed tests have low diagnostic yield in the setting of transient loss of consciousness (T-LOC). We estimated the use and cost of inappropriate investigations in patients admitted with T-LOC and assessed if these patients were given a definitive diagnosis for their presentation. We identified 80 consecutive patients admitted with T-LOC to a university teaching hospital. Eighty-eight percent (70\\/80) had a computerized topography (CT) brain scan and 49% (34\\/70) of these scans were inappropriate based on standard guidelines. Almost half (17\\/80) of electroencephalograms (EEG) and 82% (9\\/11) of carotid doppler ultrasound performed were not based on clinical evidence of seizure or stroke respectively. Forty-four percent (35\\/80) of patients had no formal diagnosis documented for their presentation. Inappropriate investigation in T-LOC is very prevalent in the acute hospital, increasing cost of patient care. In addition, there is poor diagnostic formulation for T-LOC making recurrent events more likely in the absence of definitive diagnoses

Automatic brain caudate nuclei segmentation and classification in diagnostic of Attention-Deficit/Hyperactivity Disorder.

Science.gov (United States)

Igual, Laura; Soliva, Joan Carles; Escalera, Sergio; Gimeno, Roger; Vilarroya, Oscar; Radeva, Petia

2012-12-01

We present a fully automatic diagnostic imaging test for Attention-Deficit/Hyperactivity Disorder diagnosis assistance based on previously found evidences of caudate nucleus volumetric abnormalities. The proposed method consists of different steps: a new automatic method for external and internal segmentation of caudate based on Machine Learning methodologies; the definition of a set of new volume relation features, 3D Dissociated Dipoles, used for caudate representation and classification. We separately validate the contributions using real data from a pediatric population and show precise internal caudate segmentation and discrimination power of the diagnostic test, showing significant performance improvements in comparison to other state-of-the-art methods. Copyright © 2012 Elsevier Ltd. All rights reserved.

The diagnostic accuracy of three rapid diagnostic tests for typhoid fever at Chittagong Medical College Hospital, Chittagong, Bangladesh.

Science.gov (United States)

Maude, Rapeephan R; de Jong, Hanna K; Wijedoru, Lalith; Fukushima, Masako; Ghose, Aniruddha; Samad, Rasheda; Hossain, Mohammed Amir; Karim, Mohammed Rezaul; Faiz, Mohammed Abul; Parry, Christopher M

2015-10-01

To determine the diagnostic accuracy of three rapid diagnostic tests (RDTs) for typhoid fever in febrile hospitalised patients in Bangladesh. Febrile adults and children admitted to Chittagong Medical College Hospital, Bangladesh, were investigated with Bact/Alert(®) blood cultures and real-time PCR to detect Salmonella enterica Typhi and Paratyphi A and assays for Rickettsia, leptospirosis and dengue fever. Acute serum samples were examined with the LifeAssay (LA) Test-it™ Typhoid IgM lateral flow assay detecting IgM antibodies against S. Typhi O antigen, CTKBiotech Onsite Typhoid IgG/IgM Combo Rapid-test cassette lateral flow assay detecting IgG and IgM antibodies against S. Typhi O and H antigens and SD Bioline line assay for IgG and IgM antibodies against S. Typhi proteins. In 300 malaria smear-negative febrile patients [median (IQR) age of 13.5 (5-31) years], 34 (11.3%) had confirmed typhoid fever: 19 positive by blood culture for S. Typhi (three blood PCR positive) and 15 blood culture negative but PCR positive for S. Typhi in blood. The respective sensitivity and specificity of the three RDTs in patients using a composite reference standard of blood culture and/or PCR-confirmed typhoid fever were 59% and 61% for LifeAssay, 59% and 74% for the CTK IgM and/or IgG, and 24% and 96% for the SD Bioline RDT IgM and/or IgG. The LifeAssay RDT had a sensitivity of 63% and a specificity of 91% when modified with a positive cut-off of ≥2+ and analysed using a Bayesian latent class model. These typhoid RDTs demonstrated moderate diagnostic accuracies, and better tests are needed. © 2015 The Authors. Tropical Medicine & International Health Published by John Wiley & Sons Ltd.

Determination of neuronal antibodies in suspected and definite Creutzfeldt-Jakob disease.

Science.gov (United States)

Grau-Rivera, Oriol; Sánchez-Valle, Raquel; Saiz, Albert; Molinuevo, José Luis; Bernabé, Reyes; Munteis, Elvira; Pujadas, Francesc; Salvador, Antoni; Saura, Júlia; Ugarte, Antonio; Titulaer, Maarten; Dalmau, Josep; Graus, Francesc

2014-01-01

Creutzfeldt-Jakob disease (CJD) and autoimmune encephalitis with antibodies against neuronal surface antigens (NSA-abs) may present with similar clinical features. Establishing the correct diagnosis has practical implications in the management of care for these patients. To determine the frequency of NSA-abs in the cerebrospinal fluid of patients with suspected CJD and in patients with pathologically confirmed (ie, definite) CJD. A mixed prospective (suspected) and retrospective (definite) CJD cohort study was conducted in a reference center for detection of NSA-abs. The population included 346 patients with suspected CJD and 49 patients with definite CJD. Analysis of NSA-abs in cerebrospinal fluid with brain immunohistochemistry optimized for cell-surface antigens was performed. Positive cases in the suspected CJD group were further studied for antigen specificity using cell-based assays. All definite CJD cases were comprehensively tested for NSA-abs, with cell-based assays used for leucine-rich glioma-inactivated 1 (LGI1), contactin-associated protein-like 2 (CASPR2), N-methyl-d-aspartate (NMDA), and glycine (GlY) receptors. Neuronal surface antigens were detected in 6 of 346 patients (1.7%) with rapid neurologic deterioration suggestive of CJD. None of these 6 patients fulfilled the diagnostic criteria for probable or possible CJD. The target antigens included CASPR2, LGI1, NMDAR, aquaporin 4, Tr (DNER [δ/notch-like epidermal growth factor-related receptor]), and an unknown protein. Four of the patients developed rapidly progressive dementia, and the other 2 patients had cerebellar ataxia or seizures that were initially considered to be myoclonus without cognitive decline. The patient with Tr-abs had a positive 14-3-3 test result. Small cell lung carcinoma was diagnosed in the patient with antibodies against an unknown antigen. All patients improved or stabilized after appropriate treatment. None of the 49 patients with definite CJD had NSA-abs. A low, but

Automated Test Requirement Document Generation

Science.gov (United States)

1987-11-01

DIAGNOSTICS BASED ON THE PRINCIPLES OF ARTIFICIAL INTELIGENCE ", 1984 International Test Conference, 01Oct84, (A3, 3, Cs D3, E2, G2, H2, 13, J6, K) 425...j0O GLOSSARY OF ACRONYMS 0 ABBREVIATION DEFINITION AFSATCOM Air Force Satellite Communication Al Artificial Intelligence ASIC Application Specific...In-Test Equipment (BITE) and AI ( Artificial Intelligence) - Expert Systems - need to be fully applied before a completely automated process can be

Systematic Review of Health Economic Evaluations of Diagnostic Tests in Brazil: How accurate are the results?

Science.gov (United States)

Oliveira, Maria Regina Fernandes; Leandro, Roseli; Decimoni, Tassia Cristina; Rozman, Luciana Martins; Novaes, Hillegonda Maria Dutilh; De Soárez, Patrícia Coelho

2017-08-01

The aim of this study is to identify and characterize the health economic evaluations (HEEs) of diagnostic tests conducted in Brazil, in terms of their adherence to international guidelines for reporting economic studies and specific questions in test accuracy reports. We systematically searched multiple databases, selecting partial and full HEEs of diagnostic tests, published between 1980 and 2013. Two independent reviewers screened articles for relevance and extracted the data. We performed a qualitative narrative synthesis. Forty-three articles were reviewed. The most frequently studied diagnostic tests were laboratory tests (37.2%) and imaging tests (32.6%). Most were non-invasive tests (51.2%) and were performed in the adult population (48.8%). The intended purposes of the technologies evaluated were mostly diagnostic (69.8%), but diagnosis and treatment and screening, diagnosis, and treatment accounted for 25.6% and 4.7%, respectively. Of the reviewed studies, 12.5% described the methods used to estimate the quantities of resources, 33.3% reported the discount rate applied, and 29.2% listed the type of sensitivity analysis performed. Among the 12 cost-effectiveness analyses, only two studies (17%) referred to the application of formal methods to check the quality of the accuracy studies that provided support for the economic model. The existing Brazilian literature on the HEEs of diagnostic tests exhibited reasonably good performance. However, the following points still require improvement: 1) the methods used to estimate resource quantities and unit costs, 2) the discount rate, 3) descriptions of sensitivity analysis methods, 4) reporting of conflicts of interest, 5) evaluations of the quality of the accuracy studies considered in the cost-effectiveness models, and 6) the incorporation of accuracy measures into sensitivity analyses.

LOGICAL CONDITIONS ANALYSIS METHOD FOR DIAGNOSTIC TEST RESULTS DECODING APPLIED TO COMPETENCE ELEMENTS PROFICIENCY

Directory of Open Access Journals (Sweden)

V. I. Freyman

2015-11-01

Full Text Available Subject of Research.Representation features of education results for competence-based educational programs are analyzed. Solution importance of decoding and proficiency estimation for elements and components of discipline parts of competences is shown. The purpose and objectives of research are formulated. Methods. The paper deals with methods of mathematical logic, Boolean algebra, and parametrical analysis of complex diagnostic test results, that controls proficiency of some discipline competence elements. Results. The method of logical conditions analysis is created. It will give the possibility to formulate logical conditions for proficiency determination of each discipline competence element, controlled by complex diagnostic test. Normalized test result is divided into noncrossing zones; a logical condition about controlled elements proficiency is formulated for each of them. Summarized characteristics for test result zones are imposed. An example of logical conditions forming for diagnostic test with preset features is provided. Practical Relevance. The proposed method of logical conditions analysis is applied in the decoding algorithm of proficiency test diagnosis for discipline competence elements. It will give the possibility to automate the search procedure for elements with insufficient proficiency, and is also usable for estimation of education results of a discipline or a component of competence-based educational program.

Towards Modernizing the Characterization of Shock and Detonation Physics Performance via Novel Diagnostics and Tests

Science.gov (United States)

Salyer, Terry

2017-06-01

For the bulk of detonation performance experiments, a fairly basic set of diagnostic techniques has evolved as the standard for acquiring the necessary measurements. Gold standard techniques such as pin switches and streak cameras still produce the high-quality data required, yet much room remains for improvement with regard to ease of use, cost of fielding, breadth of data, and diagnostic versatility. Over the past several years, an alternate set of diagnostics has been under development to replace many of these traditional techniques. Pulse Correlation Reflectometry (PCR) is a capable substitute for pin switches with the advantage of obtaining orders of magnitude more data at a small fraction of the cost and fielding time. Spectrally Encoded Imaging (SEI) can replace most applications of streak camera with the advantage of imaging surfaces through a single optical fiber that are otherwise optically inaccessible. Such diagnostics advance the measurement state of the art, but even further improvements may come through revamping the standardized tests themselves such as the copper cylinder expansion test. At the core of this modernization, the aforementioned diagnostics play a significant role in revamping and improving the standard test suite for the present era. This research was performed under the auspices of the United States Department of Energy.

Empirical evidence of design-related bias in studies of diagnostic tests

NARCIS (Netherlands)

Lijmer, J. G.; Mol, B. W.; Heisterkamp, S.; Bonsel, G. J.; Prins, M. H.; van der Meulen, J. H.; Bossuyt, P. M.

1999-01-01

CONTEXT: The literature contains a large number of potential biases in the evaluation of diagnostic tests. Strict application of appropriate methodological criteria would invalidate the clinical application of most study results. OBJECTIVE: To empirically determine the quantitative effect of study

Proceedings on US-Japan workshop A-56 'irradiation effects on plasma diagnostic equipment'

International Nuclear Information System (INIS)

1986-06-01

This is a collection of abstracts and papers for the US-Japan Workshop A-56 on ''Irradiation Effects on Plasma Diagnostic Equipments'' held at the Institute of Plasma Physics, Nagoya University, on January 28 through 30, 1986. The topics presented at the workshop are classified as follows: 1) Definition of the problems and general views. 2) Radiation levels estimated from recent experiments and analysis on large tokamaks. 3) Radiation sensitivities of diagnostic components. 4) Neutron sources for irradiation testing. 5) Discussion on suggested experiments on radiation hardening and conclusions. The conclusions summarized by Dr. K. M. Young are also included. (author)

An Indian test facility to characterise diagnostic neutral beam for ITER

International Nuclear Information System (INIS)

Singh, M.J.; Bandyopadhyay, M.; Rotti, C.; Singh, N.P.; Shah, Sejal; Bansal, G.; Gahlaut, A.; Soni, J.; Lakdawala, H.; Waghela, Harshad; Ahmed, I.; Roopesh, G.; Baruah, U.K.; Chakraborty, A.K.

2011-01-01

The diagnostic neutral beam (DNB) line shall be used to diagnose the He ash content in the D-T phase of the ITER machine using the charge exchange recombination spectroscopy (CXRS). Implementation of a successful DNB at ITER requires several challenges related to the production, neutralization and transport of the neutral beam over path lengths of 20.665 m, to be overcome. The delivery is aided if the above effects are tested prior to onsite commissioning. As DNB is a procurement package for INDIA, an ITER approved Indian test facility, INTF, is under construction at Institute for Plasma Research (IPR), India and is envisaged to be operational in 2015. The timeline for this facility is synchronized with the RADI, ELISE (IPP, Garching), SPIDER (RFX, Padova) in a manner that best utilization of configurational inputs available from them are incorporated in the design. This paper describes the facility in detail and discusses the experiments planned to optimise the beam transmission and testing of the beam line components using various diagnostics.

[The Offer of Medical-Diagnostic Self-Tests on German Language Websites: Results of a Systematic Internet Search].

Science.gov (United States)

Kuecuekbalaban, P; Schmidt, S; Muehlan, H

2018-03-01

The aim of the current study was to provide an overview of medical-diagnostic self-tests which can be purchased without a medical prescription on German language websites. From September 2014 to March 2015, a systematic internet research was conducted with the following search terms: self-test, self-diagnosis, home test, home diagnosis, quick test, rapid test. 513 different self-tests for the diagnostics of 52 diverse diseases or health risks were identified, including chronic diseases (e. g. diabetes, chronic disease of the kidneys, liver, and lungs), sexually transmitted diseases (e. g. HIV, chlamydia, gonorrhea), infectious diseases (e. g. tuberculosis, malaria, Helicobacter pylori), allergies (e. g. house dust, cats, histamine) and cancer as well as tests for the diagnostics of 12 different psychotropic substances. These were sold by 90 companies in Germany and by other foreign companies. The number of medical-diagnostic self-tests which can be bought without a medical prescription on the Internet has increased enormously in the last 10 years. Further studies are needed for the identification of the determinants of the use of self-tests as well as the impact of the application on the experience and behavior of the user. © Georg Thieme Verlag KG Stuttgart · New York.

Estimating diagnostic test accuracies for Brachyspira hyodysenteriae accounting for the complexities of population structure in food animals.

Directory of Open Access Journals (Sweden)

Sonja Hartnack

Full Text Available For swine dysentery, which is caused by Brachyspira hyodysenteriae infection and is an economically important disease in intensive pig production systems worldwide, a perfect or error-free diagnostic test ("gold standard" is not available. In the absence of a gold standard, Bayesian latent class modelling is a well-established methodology for robust diagnostic test evaluation. In contrast to risk factor studies in food animals, where adjustment for within group correlations is both usual and required for good statistical practice, diagnostic test evaluation studies rarely take such clustering aspects into account, which can result in misleading results. The aim of the present study was to estimate test accuracies of a PCR originally designed for use as a confirmatory test, displaying a high diagnostic specificity, and cultural examination for B. hyodysenteriae. This estimation was conducted based on results of 239 samples from 103 herds originating from routine diagnostic sampling. Using Bayesian latent class modelling comprising of a hierarchical beta-binomial approach (which allowed prevalence across individual herds to vary as herd level random effect, robust estimates for the sensitivities of PCR and culture, as well as for the specificity of PCR, were obtained. The estimated diagnostic sensitivity of PCR (95% CI and culture were 73.2% (62.3; 82.9 and 88.6% (74.9; 99.3, respectively. The estimated specificity of the PCR was 96.2% (90.9; 99.8. For test evaluation studies, a Bayesian latent class approach is well suited for addressing the considerable complexities of population structure in food animals.

Diagnostic uncertainty, guilt, mood, and disability in back pain.

Science.gov (United States)

Serbic, Danijela; Pincus, Tamar; Fife-Schaw, Chris; Dawson, Helen

2016-01-01

In the majority of patients a definitive cause for low back pain (LBP) cannot be established, and many patients report feeling uncertain about their diagnosis, accompanied by guilt. The relationship between diagnostic uncertainty, guilt, mood, and disability is currently unknown. This study tested 3 theoretical models to explore possible pathways between these factors. In Model 1, diagnostic uncertainty was hypothesized to correlate with pain-related guilt, which in turn would positively correlate with depression, anxiety and disability. Two alternative models were tested: (a) a path from depression and anxiety to guilt, from guilt to diagnostic uncertainty, and finally to disability; (b) a model in which depression and anxiety, and independently, diagnostic uncertainty, were associated with guilt, which in turn was associated with disability. Structural equation modeling was employed on data from 413 participants with chronic LBP. All 3 models showed a reasonable-to-good fit with the data, with the 2 alternative models providing marginally better fit indices. Guilt, and especially social guilt, was associated with disability in all 3 models. Diagnostic uncertainty was associated with guilt, but only moderately. Low mood was also associated with guilt. Two newly defined factors, pain related guilt and diagnostic uncertainty, appear to be linked to disability and mood in people with LBP. The causal path of these links cannot be established in this cross sectional study. However, pain-related guilt especially appears to be important, and future research should examine whether interventions directly targeting guilt improve outcomes. (c) 2015 APA, all rights reserved).

Metabolic syndrome in Mexican children: Low effectiveness of diagnostic definitions.

Science.gov (United States)

Peña-Espinoza, Barbara Itzel; Granados-Silvestre, María de Los Ángeles; Sánchez-Pozos, Katy; Ortiz-López, María Guadalupe; Menjivar, Marta

Early identification of children with metabolic syndrome (MS) is essential to decrease the risk of developing diabetes and cardiovascular disease in adulthood. Detection of MS is however challenging because of the different definitions for diagnosis; as a result, preventive actions are not taken in some children at risk. The study objective was therefore to compare prevalence of MS in children according to the IDF, NCEP-ATP-III, Cook, de Ferranti and Weiss definitions, considering insulin resistance (IR) markers such as HOMA-IR and/or metabolic index (MI). A total of 508 Mexican children (aged 9 to 13 years) from seven schools were enrolled in a cross-sectional study. Somatometric, biochemical, and hormonal measurements were evaluated. Frequency of MS was 2.4-45.9% depending on the definition used. Frequency of IR in children not diagnosed with MS was 12.4-25.2% using HOMA-IR and 4.0-16.3% using MI. When HOMA-IR or MI was included in each of the definitions, frequency of MS was 8.5-50.2% and 7.7-46.9% respectively. The kappa value including HOMA-IR and/or MI was greater than 0.8. This study demonstrated the poor effectiveness of the current criteria used to diagnose MS in Mexican children, as shown by the variability in the definitions and by the presence of IR in children who not diagnosed with MS. Inclusion of HOMA-IR and/or MI in definitions of MS (thus increasing agreement between them) decreases the chance of excluding children at risk and allows for MS prevalence between populations. Copyright © 2017 SEEN y SED. Publicado por Elsevier España, S.L.U. All rights reserved.

The value of diagnostic information to patients with suspected multiple sclerosis. Rochester-Toronto MRI Study Group.

Science.gov (United States)

Mushlin, A I; Mooney, C; Grow, V; Phelps, C E

1994-01-01

To determine the value of diagnostic information to patients with suspected multiple sclerosis (MS). Because treatment choices would be only minimally affected by earlier diagnosis for most patients with this clinical problem, this study assessed the "nondecisional" value of diagnosis. Prospective survey of patients before and after diagnostic workup, including imaging with magnetic resonance scanning. We assessed the effect of diagnostic information on patients' sense of well-being, as well as direct measures of the utility of information (using time trade-off and willingness-to-pay techniques). Patients referred from primary care practices for diagnostic workup for suspected MS to neurology clinics and practices. Sixty-eight individuals, mean age 37.5 years, 53 female and 15 male. Thirty-one patients were classified as having "probable MS," and 37 were classified as having "possible MS" by the examining neurologist before workup. Present and future health perception, uncertainty about diagnosis-prognosis, and level of anxiety. Willingness to pay for diagnostic information, quality of life as measured by the time trade-off technique, and psychological state of the patient before and after diagnosis. Diagnostic uncertainty fell significantly as a result of the diagnostic workup. Most patients (59/62) said that they were better off having received diagnostic information. Although anxiety seemed to be reduced by testing, overall anxiety levels did not decrease as much as anticipated. Patients also became less optimistic about their future health after testing. On average, patients were willing to forgo 4.5 quality-adjusted life days to receive an earlier diagnosis and their quality of life after diagnosis improved slightly. Subgroups of patients differed in their response to diagnostic information. Those in whom no definitive diagnosis emerged tend to be more anxious rather than being reassured by the "negative" workup. Individuals with "positive" workups became less

Diagnostic x-ray equipment compliance and facility survey. Recommended procedures for equipment and facility testing

International Nuclear Information System (INIS)

1994-01-01

The Radiation Protection Bureau has set out guidelines for the testing of diagnostic x-ray equipment and facilities. This guide provides information for the x-ray inspector, test engineer, technologist, medical physicist and any other person responsible for verifying the regulatory compliance or safety of diagnostic x-ray equipment and facilities. Diagnostic x-radiation is an essential part of present day medical practice. The largest contributor of irradiation to the general population comes from diagnostic x-radiation. Although individual irradiations are usually small, there is a concern of possible excess cancer risk when large populations are irradiated. Unnecessary irradiations to patients from radiological procedures can be significantly reduced with little or no decrease in the value of medical diagnostic information. This can be achieved by using well designed x-ray equipment which is installed, used and maintained by trained personnel, and by the adoption of standardized procedures. In general, when patient surface dose is reduced, there is a corresponding decrease in dose to x-ray equipment operators and other health care personnel. 2 tabs., 4 figs

Diagnostic x-ray equipment compliance and facility survey. Recommended procedures for equipment and facility testing

Energy Technology Data Exchange (ETDEWEB)

NONE

1994-12-31

The Radiation Protection Bureau has set out guidelines for the testing of diagnostic x-ray equipment and facilities. This guide provides information for the x-ray inspector, test engineer, technologist, medical physicist and any other person responsible for verifying the regulatory compliance or safety of diagnostic x-ray equipment and facilities. Diagnostic x-radiation is an essential part of present day medical practice. The largest contributor of irradiation to the general population comes from diagnostic x-radiation. Although individual irradiations are usually small, there is a concern of possible excess cancer risk when large populations are irradiated. Unnecessary irradiations to patients from radiological procedures can be significantly reduced with little or no decrease in the value of medical diagnostic information. This can be achieved by using well designed x-ray equipment which is installed, used and maintained by trained personnel, and by the adoption of standardized procedures. In general, when patient surface dose is reduced, there is a corresponding decrease in dose to x-ray equipment operators and other health care personnel. 2 tabs., 4 figs.

[Critical reading of articles about diagnostic tests (part I): Are the results of the study valid?].

Science.gov (United States)

Arana, E

2015-01-01

In the era of evidence-based medicine, one of the most important skills a radiologist should have is the ability to analyze the diagnostic literature critically. This tutorial aims to present guidelines for determining whether primary diagnostic articles are valid for clinical practice. The following elements should be evaluated: whether the study can be applied to clinical practice, whether the technique was compared to the reference test, whether an appropriate spectrum of patients was included, whether expectation bias and verification bias were limited, the reproducibility of the study, the practical consequences of the study, the confidence intervals for the parameters analyzed, the normal range for continuous variables, and the placement of the test in the context of other diagnostic tests. We use elementary practical examples to illustrate how to select and interpret the literature on diagnostic imaging and specific references to provide more details. Copyright © 2014 SERAM. Published by Elsevier España, S.L.U. All rights reserved.

A hybrid model for combining case-control and cohort studies in systematic reviews of diagnostic tests

Science.gov (United States)

Chen, Yong; Liu, Yulun; Ning, Jing; Cormier, Janice; Chu, Haitao

2014-01-01

Systematic reviews of diagnostic tests often involve a mixture of case-control and cohort studies. The standard methods for evaluating diagnostic accuracy only focus on sensitivity and specificity and ignore the information on disease prevalence contained in cohort studies. Consequently, such methods cannot provide estimates of measures related to disease prevalence, such as population averaged or overall positive and negative predictive values, which reflect the clinical utility of a diagnostic test. In this paper, we propose a hybrid approach that jointly models the disease prevalence along with the diagnostic test sensitivity and specificity in cohort studies, and the sensitivity and specificity in case-control studies. In order to overcome the potential computational difficulties in the standard full likelihood inference of the proposed hybrid model, we propose an alternative inference procedure based on the composite likelihood. Such composite likelihood based inference does not suffer computational problems and maintains high relative efficiency. In addition, it is more robust to model mis-specifications compared to the standard full likelihood inference. We apply our approach to a review of the performance of contemporary diagnostic imaging modalities for detecting metastases in patients with melanoma. PMID:25897179

Beam diagnostic tools for the negative hydrogen ion source test facility ELISE

International Nuclear Information System (INIS)

Nocentini, Riccardo; Fantz, Ursel; Franzen, Peter; Froeschle, Markus; Heinemann, Bernd; Riedl, Rudolf; Ruf, Benjamin; Wuenderlich, Dirk

2013-01-01

Highlights: ► We present an overview of beam diagnostic tools foreseen for the new testbed ELISE. ► A sophisticated diagnostic calorimeter allows beam profile measurement. ► A tungsten wire mesh in the beam path provides a qualitative picture of the beam. ► Stripping losses and beam divergence are measured by H α Doppler shift spectroscopy. -- Abstract: The test facility ELISE, presently being commissioned at IPP, is a first step in the R and D roadmap for the RF driven ion source and extraction system of the ITER NBI system. The “half-size” ITER-like test facility includes a negative hydrogen ion source that can be operated for 1 h. ELISE is expected to extract an ion beam of 20 A at 60 kV for 10 s every 3 min, therefore delivering a total power of 1.2 MW. The extraction area has a geometry that closely reproduces the ITER design, with the same width and half the height, i.e. 1 m × 1 m. This paper presents an overview of beam diagnostic tools foreseen for ELISE. For the commissioning phase, a simple beam dump with basic diagnostic capabilities has been installed. In the second phase, the beam dump will be substituted by a more sophisticated diagnostic calorimeter to allow beam profile measurement. Additionally, a tungsten wire mesh will be introduced in the beam path to provide a qualitative picture of beam size and position. Stripping losses and beam divergence will be measured by means of H α Doppler shift spectroscopy. An absolute calibration is foreseen in order to measure beam intensity

Assessment of the Diagnostic Potential of Clinotech TB Screen Test ...

African Journals Online (AJOL)

The Clinotech TB Screen test, a 3rd generation multi-antigen rapid chromatographic immunoassay for detection of IgG antibodies in serum against recombinant protein antigens 38kDa, 16kDa and 6kDa, was assessed for its diagnostic potential for diagnosis of active pulmonary TB in routine TB control programme in Abia ...

Interlaboratory comparison and accreditation in quality control testing of diagnostic X-ray equipment

International Nuclear Information System (INIS)

Kepler, K.; Vladimirov, A.; Servomaa, A.

2005-01-01

The Univ. of Tartu provides a quality control service to the majority of diagnostic X-ray departments in Estonia. Its methodology has been adopted from the IEC and other relevant standards. Recently the Testing Centre of the Univ. of Tartu was accredited on this methodology by ISO/IEC 17025. Besides the implementation of the quality management system, participation in interlaboratory comparison (ILC) was one of the prerequisites for the accreditation. Tests for estimating reproducibility of tube voltage and dose rate, accuracy of the voltage and accuracy of exposure time were carried out on a diagnostic X-ray unit in the Radiation and Nuclear Safety Authority in Helsinki. The measurement performance was judged by calculating deviation En normalised with respect to the stated uncertainties. En values for all tests were less than unity and by the common ILC criteria the testing performance could be considered as acceptable. (authors)

Translating microarray data for diagnostic testing in childhood leukaemia

International Nuclear Information System (INIS)

Hoffmann, Katrin; Firth, Martin J; Beesley, Alex H; Klerk, Nicholas H de; Kees, Ursula R

2006-01-01

Recent findings from microarray studies have raised the prospect of a standardized diagnostic gene expression platform to enhance accurate diagnosis and risk stratification in paediatric acute lymphoblastic leukaemia (ALL). However, the robustness as well as the format for such a diagnostic test remains to be determined. As a step towards clinical application of these findings, we have systematically analyzed a published ALL microarray data set using Robust Multi-array Analysis (RMA) and Random Forest (RF). We examined published microarray data from 104 ALL patients specimens, that represent six different subgroups defined by cytogenetic features and immunophenotypes. Using the decision-tree based supervised learning algorithm Random Forest (RF), we determined a small set of genes for optimal subgroup distinction and subsequently validated their predictive power in an independent patient cohort. We achieved very high overall ALL subgroup prediction accuracies of about 98%, and were able to verify the robustness of these genes in an independent panel of 68 specimens obtained from a different institution and processed in a different laboratory. Our study established that the selection of discriminating genes is strongly dependent on the analysis method. This may have profound implications for clinical use, particularly when the classifier is reduced to a small set of genes. We have demonstrated that as few as 26 genes yield accurate class prediction and importantly, almost 70% of these genes have not been previously identified as essential for class distinction of the six ALL subgroups. Our finding supports the feasibility of qRT-PCR technology for standardized diagnostic testing in paediatric ALL and should, in conjunction with conventional cytogenetics lead to a more accurate classification of the disease. In addition, we have demonstrated that microarray findings from one study can be confirmed in an independent study, using an entirely independent patient cohort

The psychological impact of test results following diagnostic coronary CT angiography.

Science.gov (United States)

Devcich, Daniel A; Ellis, Christopher J; Broadbent, Elizabeth; Gamble, Greg; Petrie, Keith J

2012-11-01

Coronary computed tomography (CT) angiography is an advanced cardiac imaging test commonly used for diagnosing early signs of ischemic heart disease. Despite its importance in cardiology, little is known about its psychological effect on patients. The present study sought to examine these effects in relation to illness perceptions, cardiac health behavior intentions, and subsequent health behaviors. Forty-five nonacute cardiac patients who were referred for diagnostic coronary CT angiography completed questionnaires prior to testing and following the receipt of test results, at which point illness perceptions and intentions to take cardiac medication, as well as diet and exercise intentions were measured. Exercise and dietary behaviors were measured at follow-up 6 weeks later. Changes on these variables were then compared between patients diagnosed with normal arteries and patients diagnosed with diseased arteries. Compared to positive-testing patients, patients with normal test results reported significant changes toward more positive illness perceptions following testing, with improvements in emotional effect of illness, illness concern, consequences, and personal control of illness. The illness perception of treatment control was seen as more important among positive-testing patients, whereas both groups reported increases in illness coherence. Health behavior intentions (cardiac medication intentions and exercise intentions) increased for positive-testing patients only, as did physical activity at follow-up. Diagnosis-dependent psychological effects can be detected following coronary CT angiography. These effects have important implications for patient health and health care in diagnostic contexts, and the results from this study can be used to guide further research in this area.

An evidence-based definition of lifelong premature ejaculation: report of the International Society for Sexual Medicine Ad Hoc Committee for the Definition of Premature Ejaculation

NARCIS (Netherlands)

McMahon, Chris G.; Althof, Stanley; Waldinger, Marcel D.; Porst, Hartmut; Dean, John; Sharlip, Ira; Adaikan, P. G.; Becher, Edgardo; Broderick, Gregory A.; Buvat, Jacques; Dabees, Khalid; Giraldi, Annamaria; Giuliano, François; Hellstrom, Wayne J. G.; Incrocci, Luca; Laan, Ellen; Meuleman, Eric; Perelman, Michael A.; Rosen, Raymond; Rowland, David; Segraves, Robert

2008-01-01

To develop a contemporary, evidence-based definition of premature ejaculation (PE). There are several definitions of PE; the most commonly quoted, the American Psychiatric Association's Diagnostic and Statistical Manual of Mental Disorders - 4th Edition - Text Revision, and other definitions of PE,

Diagnostic accuracy and optimal use of three tests for tuberculosis in live badgers.

Directory of Open Access Journals (Sweden)

Julian A Drewe

Full Text Available BACKGROUND: Accurate diagnosis of tuberculosis (TB due to infection with Mycobacterium bovis is notoriously difficult in live animals, yet important if we are to understand the epidemiology of TB and devise effective strategies to limit its spread. Currently available tests for diagnosing TB in live Eurasian badgers (Meles meles remain unvalidated against a reliable gold standard. The aim of the present study was to evaluate the diagnostic accuracy and optimal use of three tests for TB in badgers in the absence of a gold standard. METHODOLOGY/PRINCIPAL FINDINGS: A Bayesian approach was used to evaluate the diagnostic accuracy and optimal use of mycobacterial culture, gamma-interferon assay and a commercially available serological test using multiple samples collected from 305 live wild badgers. Although no single test was judged to be sufficiently sensitive and specific to be used as a sole diagnostic method, selective combined use of the three tests allowed guidelines to be formulated that allow a diagnosis to be made for individual animals with an estimated overall accuracy of 93% (range: 75% to 97%. Employing this approach in the study population of badgers resulted in approximately 13 out of 14 animals having their true infection status correctly classified from samples collected on a single capture. CONCLUSIONS/SIGNIFICANCE: This method of interpretation represents a marked improvement on the current procedure for diagnosing M. bovis infection in live badgers. The results should be of use to inform future test and intervention strategies with the aim of reducing the incidence of TB in free-living wild badger populations.

An evidence-based definition of lifelong premature ejaculation: report of the International Society for Sexual Medicine (ISSM) ad hoc committee for the definition of premature ejaculation

NARCIS (Netherlands)

McMahon, Chris G.; Althof, Stanley E.; Waldinger, Marcel D.; Porst, Hartmut; Dean, John; Sharlip, Ira D.; Adaikan, P. G.; Becher, Edgardo; Broderick, Gregory A.; Buvat, Jacques; Dabees, Khalid; Giraldi, Annamaria; Giuliano, François; Hellstrom, Wayne J. G.; Incrocci, Luca; Laan, Ellen; Meuleman, Eric; Perelman, Michael A.; Rosen, Raymond C.; Rowland, David L.; Segraves, Robert

2008-01-01

The medical literature contains several definitions of premature ejaculation (PE). The most commonly quoted definition, the American Psychiatric Association's Diagnostic and Statistical Manual of Mental Disorders-Fourth Edition-Text Revision, and other definitions of PE are all authority based

An evidence-based definition of lifelong premature ejaculation: Report of the International Society for Sexual Medicine (ISSM) Ad Hoc Committee for the Definition of Premature Ejaculation

DEFF Research Database (Denmark)

McMahon, C.G.; Althof, S.E.; Waldinger, M.D.

2008-01-01

Introduction. The medical literature contains several definitions of premature ejaculation (PE). The most commonly quoted definition, the American Psychiatric Association's Diagnostic and Statistical Manual of Mental Disorders-Fourth Edition-Text Revision, and other definitions of PE are all auth...

Comparison of different criteria for periodontitis case definition in head and neck cancer individuals.

Science.gov (United States)

Bueno, Audrey Cristina; Ferreira, Raquel Conceição; Cota, Luis Otávio Miranda; Silva, Guilherme Carvalho; Magalhães, Cláudia Silami; Moreira, Allyson Nogueira

2015-09-01

Different periodontitis case definitions have been used in clinical research and epidemiology. The aim of this study was to determine more accurate criterion for the definition of mild and moderate periodontitis case to be applied to head and neck cancer individuals before radiotherapy. The frequency of periodontitis in a sample of 84 individuals was determined according to different diagnostic criteria: (1) Lopez et al. (2002);(2) Hujoel et al. (2006); (3) Beck et al. (1990); (4) Machtei et al. (1992); (5) Tonetti and Claffey (2005); (6) and Page and Eke (2007). All diagnosis were based on the clinical parameters obtained by a single calibrated examiner (Kw = 0.71). The individuals were evaluated before radiotherapy. They received oral hygiene instructions, and the cases diagnosed with periodontitis (Page and Eke 2007) were treated. The gold standard was the definition 6, and the others were compared by means of agreement, sensitivity (SS), specificity (SP), and the area under ROC curve. The kappa test evaluated the agreement between definitions. The frequency of periodontitis at baseline was 53.6 % (definition 1), 81.0 % (definition 2), 40.5 % (definition 3), 26.2 % (definition 4), 13.1 % (definition 5), and 70.2 % (definition 6). The kappa test showed a moderate agreement between definitions 6 and 2 (59.0 %) and definitions 6 and 1 (56.0 %). The criterion with higher SS (0.92) and SP (0.73) was definition 1. Definition 1 was the most accurate criterion to case periodontitis definition to be applied to head and neck cancer individuals.

Consensus based reporting standards for diagnostic test accuracy studies for paratuberculosis in ruminants.

NARCIS (Netherlands)

Gardner, I.A.; Nielsen, S.S.; Whittington, R.J.; Collins, M.T.; Bakker, D.; Harris, B.; Sreevatsan, S.; Lombard, J.E.; Sweeney, R.; Smith, D.R.; Gavalchin, J.; Eda, S.

2011-01-01

The Standards for Reporting of Diagnostic Accuracy (STARD) statement (www.stard-statement.org) was developed to encourage complete and transparent reporting of key elements of test accuracy studies in human medicine. The statement was motivated by widespread evidence of bias in test accuracy studies

Diagnostic tests for Helicobacter pylori : A prospective evaluation of their accuracy, without selecting a single test as the gold standard

NARCIS (Netherlands)

Thijs, J C; van Zwet, A A; Thijs, W J; Oey, H B; Karrenbeld, A; Stellaard, F; Luijt, D S; Meyer, B C; Kleibeuker, J H

1996-01-01

OBJECTIVE: To assess the accuracy of six commonly used diagnostic tests for Helicobacter pylori in a prospective study without using any specific test as the gold standard (the patient was regarded as H. pylori-infected if two or more tests, whatever their nature, were positive). METHODS: In 105

Continuous-data diagnostic tests for paratuberculosis as a multistage disease

DEFF Research Database (Denmark)

Toft, Nils; Nielsen, Søren Saxmose; Jørgensen, Erik

2005-01-01

We devised a general method for interpretation of multistage diseases using continuous-data diagnostic tests. As an example, we used paratuberculosis as a multistage infection with 2 stages of infection as well as a noninfected state. Using data from a Danish research project, a fecal culture...... testing scheme was linked to an indirect ELISA and adjusted for covariates (parity, age at first calving, and days in milk). We used the log-transformed optical densities in a Bayesian network to obtain the probabilities for each of the 3 infection stages for a given optical density (adjusted...... for covariates). The strength of this approach was that the uncertainty associated with a test was imposed directly on the individual test result rather than aggregated into the population-based measures of test properties (i.e., sensitivity and specificity)...

The diagnostic effects of s-TSH and TRH stimulating test on subclinical thyroid function

International Nuclear Information System (INIS)

Lu Shujun; Wang Wenliang; Lu Shuyan; Zheng Linong; Hu Changjun; Fang Xiaozheng; Zheng Huian; Ma Meizhen

2002-01-01

The study was carried out to investigate the diagnostic effects of supersensitive TSH on diagnosing subclinical thyroid function with only once s-TSH detection and with TRH stimulating tests. TRH stimulating tests have been undertaken for 90 patients with different thyroid disease and 58 normal subjects. Diagnostic basal levels of s-TSH test in control group, subclinical hyperthyroidism group and subclinical hypothyroidism group were 2.20 +- 1.85 mIU/L, 0.54 +- 0.3 mIU/L and 9.08 +- 6.3 mIU/L, respectively, the levels of subclinical hyperthyroidism and subclinical hypothyroidism group were significantly higher than that of normal subjects group (P s -TSH>30 mIU/L. Dynamic observing of TRH stimulating tests have more effect than that of only once s-TSH detection in diagnosing subclinical thyroid function

Temporal evolution of acute respiratory distress syndrome definitions

Directory of Open Access Journals (Sweden)

José R. Fioretto

2013-11-01

Conclusions: ARDS is a serious disease that remains an ongoing diagnostic and therapeutic challenge. The evolution of definitions used to describe the disease shows that studies are needed to validate the current definition, especially in pediatrics, where the data are very scarce.

Protease activity measurement in milk as a diagnostic test for clinical mastitis in dairy cows

NARCIS (Netherlands)

Koop, G.; van Werven, T.; Roffel, S.; Hogeveen, H.; Nazmi, K.; Bikker, F.J.

2015-01-01

Due to the increasing use of automated milking systems, automated detection of clinical mastitis is becoming more important. Various in- or on-line diagnostic tests are in use, but generally suffer from false mastitis alerts. In this study, we explored a new diagnostic approach based on measurement

Evidence-based diagnostics: adult septic arthritis.

Science.gov (United States)

Carpenter, Christopher R; Schuur, Jeremiah D; Everett, Worth W; Pines, Jesse M

2011-08-01

Acutely swollen or painful joints are common complaints in the emergency department (ED). Septic arthritis in adults is a challenging diagnosis, but prompt differentiation of a bacterial etiology is crucial to minimize morbidity and mortality. The objective was to perform a systematic review describing the diagnostic characteristics of history, physical examination, and bedside laboratory tests for nongonococcal septic arthritis. A secondary objective was to quantify test and treatment thresholds using derived estimates of sensitivity and specificity, as well as best-evidence diagnostic and treatment risks and anticipated benefits from appropriate therapy. Two electronic search engines (PUBMED and EMBASE) were used in conjunction with a selected bibliography and scientific abstract hand search. Inclusion criteria included adult trials of patients presenting with monoarticular complaints if they reported sufficient detail to reconstruct partial or complete 2 × 2 contingency tables for experimental diagnostic test characteristics using an acceptable criterion standard. Evidence was rated by two investigators using the Quality Assessment Tool for Diagnostic Accuracy Studies (QUADAS). When more than one similarly designed trial existed for a diagnostic test, meta-analysis was conducted using a random effects model. Interval likelihood ratios (LRs) were computed when possible. To illustrate one method to quantify theoretical points in the probability of disease whereby clinicians might cease testing altogether and either withhold treatment (test threshold) or initiate definitive therapy in lieu of further diagnostics (treatment threshold), an interactive spreadsheet was designed and sample calculations were provided based on research estimates of diagnostic accuracy, diagnostic risk, and therapeutic risk/benefits. The prevalence of nongonococcal septic arthritis in ED patients with a single acutely painful joint is approximately 27% (95% confidence interval [CI] = 17

The furosemide diagnostic test in suspected slow-onset heart failure : popular but not useful

NARCIS (Netherlands)

Kelder, Johannes C.; Cramer, Maarten J.; Rutten, Frans H.; Plokker, H. W.; Grobbee, Diederick E.; Hoes, Arno W.

Aims Early, slow-onset heart failure is difficult to diagnose from just signs and symptoms. The physician needs ancillary diagnostic tests. The 'loop-diuretic test' or 'furosemide test', characterized as weight loss and alleviation of symptoms after a short course of a loop-diuretic, could be a

Structured approach to design of diagnostic test evaluation studies for chronic progressive infections in animals

DEFF Research Database (Denmark)

Nielsen, Søren Saxmose; Toft, Nils; Gardner, Ian Andrew

2011-01-01

Diagnostic test evaluations (DTEs) for chronic infections are challenging because a protracted incubation period has to be considered in the design of the DTE, and the adverse effects of infection may be widespread and progressive over an animal's entire life. Frequently, the specific purpose......) than originally intended. The objective of this paper is to outline a structured approach to the design and conduct of a DTE for diagnostic tests used for chronic infections in animals, and intended for different purposes. We describe the process from reflections about test purpose and the underlying...... of the test is not formally considered when a test is evaluated. Therefore, the result is often a DTE where test sensitivity and specificity estimates are biased, either because of problems with establishing the true infection status or because the test detects another aspect of the infection (and analyte...

Diagnostic Tests for The Control of Foot and Mouth Disease: An ...

African Journals Online (AJOL)

This paper describes the various diagnostic tests available for FMD, the limitations of each and their potential application in a low technology setting. The need to have complementary field and laboratory operations including suitable samples and transport methods are discussed, and examples are given. The importance of ...

Applications of optical fibers in nuclear test diagnostics

International Nuclear Information System (INIS)

Lyons, P.B.; Hodson, E.K.; Looney, L.D.

1980-01-01

Two new plasma diagnostic experiments have been successfully fielded on nuclear device tests at NTS. Both systems rely on the unique advantages provided by optical fiber technology and both systems provide new diagnostic capabilities that previously were beyond the state-of-the-art in coaxial cable systems. One system addresses the need to record e wide bandwidth data on gamma-ray sources. Over the long (< 1 km) distances that characterize NTS testing, the bandwidth of coaxial cable systems is usually limited to < 200 to 400 MHz even with extensive equalization. The new system uses the Cerenkov process to generate light in a converter material. High bandwidth fibers and detectors are used to approach a 1-GHz bandwidth. In this case fibers provided the bandwidth capability. The second system provides time and space resolution of a neutron source on a fast (ns) time scale. Previous systems have utilized either an array of neutron detectors with individual coaxial cables or a fast scintillator viewed by a gated image intensifier. For a large number of channels, the coaxial system becomes very costly and is subject to potentially severe EMI concerns. The gated intensifier system requires complex electronics and accurate timing and can be affected by EMI. An alternative system is described which provides continuous time coverage with limited spatial resolution. Complete freedom from EMI is achieved through the use of optical data collection and transmission. The optical fibers offered a major (2 to 3 times) cost savings and a large weight savings relative to the coax system. Each system is discussed

The introduction of compulsory compliance testing of medical diagnostic x-ray equipment in Western Australia

International Nuclear Information System (INIS)

Rafferty, M. W.; Jacob, C. S.

1995-01-01

Performance testing of medical diagnostic X-ray equipment can reveal equipment faults which, while not always clinically detectable, may contribute to reduced image quality and unnecessary radiation exposure of both patients and staff. Routine testing of such equipment is highly desirable to identify such faults and allows them to be rectified. The Radiological council of Western Australia is moving towards requiring compulsory compliance testing of all (new and existing) medical diagnostic X-ray equipment that all new mobile radiographic and new mammographic X-ray equipment be issued with a compliance test certificate as a prerequisite for registration. Workbooks which provide details of the tests required and recommended test methods have been prepared for medical radiographic (mobile and fixed), fluoroscopic and mammographic X-ray equipment. It is intended that future workbooks include details of the tests and methods for dental and computed tomography X-ray units. The workbooks are not limited to the compliance testing of items as specified in the Regulations, but include tests for other items such as film processing, darkrooms and image quality (for fluoroscopic equipment). Many of the workbook tests could be used within a regular quality assurance program for diagnostic X-ray equipment. Persons who conduct such compliance tests will need to be licensed and have all test certificates endorsed by a qualified expert. Suitable training and assessment of compliance testers will be required. Notification of such tests (including non-compliant items and corrective actions taken) will be required by the Radiological Council as a condition of equipment registration. 9 refs

Pearls and pitfalls of allergy diagnostic testing: report from the American College of Allergy, Asthma and Immunology/American Academy of Allergy, Asthma and Immunology Specific IgE Test Task Force.

Science.gov (United States)

Cox, Linda; Williams, Brock; Sicherer, Scott; Oppenheimer, John; Sher, Larry; Hamilton, Robert; Golden, David

2008-12-01

The intended purpose of this monograph is to provide a general overview of allergy diagnostics for health care professionals who care for patients with allergic disease. For a more comprehensive review of allergy diagnostic testing, readers can refer to the Allergy Diagnostic Practice Parameters. A key message is that a positive allergy test result (skin or blood) indicates only the presence of allergen specific IgE (called sensitization). It does not necessarily mean clinical allergy (ie, allergic symptoms with exposure). It is important for this reason that the allergy evaluation be based on the patient's history and directed by a health care professional with sufficient understanding of allergy diagnostic testing to use the information obtained from his/her evaluation of the patient to determine (1) what allergy diagnostic tests to order, (2) how to interpret the allergy diagnostic test results, and (3) how to use the information obtained from the allergy evaluation to develop an appropriate therapeutic treatment plan.

42 CFR 415.180 - Teaching setting requirements for the interpretation of diagnostic radiology and other diagnostic...

Science.gov (United States)

2010-10-01

... interpretation of diagnostic radiology and other diagnostic tests. 415.180 Section 415.180 Public Health CENTERS... for the interpretation of diagnostic radiology and other diagnostic tests. (a) General rule. Physician fee schedule payment is made for the interpretation of diagnostic radiology and other diagnostic tests...

[Pilot tests using molecular diagnostic assay cervicovaginal infection during pregnancy].

Science.gov (United States)

Beltrán-Montoya, J; Escudero-Gontes, S; Martínez-Huerta, N E; Ávila-Vergara, M A; Morales-Hernández, V; Canchola-Sotelo, C; Palacios-González, B; Vadillo-Ortega, F

2016-08-01

The prevalence of cervicovaginal infections during pregnancy has been associated with adverse perinatal outcomes however, the actual approach used for diagnosis is not effective. The aim of this study was to compare the diagnosis of vaginal infections in pregnant women using clinical, molecular diagnostic and traditional microbiological culture in a pilot study, to determine the prevalence and association with the development of preterm labor. We performed a nested cross-sectional study composed by 54 women in a cohort of pregnant women in Mexico City. Cervicovaginal infections were evaluated by clinical methods, microbiology culture and a commercially available molecular biology test. Prevalence of cervicovaginal infections during pregnancy was estimated between 28% and 50% according to methodologies. Considering the clinical diagnosis of preterm labor as the gold standard, all diagnostic tests were poor as predictors of preterm labor. Traditional approaches to establish the significance of cervicovaginal infection in pregnancy are exhausted, so be sought new ways to understand this complex relationship. Meanwhile it is recommended to continue to use traditional methods to identify infections during pregnancy in both knowledge of new methods aimed at understanding these relationships are sophisticated.

International definition of a point-of-care test in family practice: a modified e-Delphi procedure.

Science.gov (United States)

Schols, Angel M R; Dinant, Geert-Jan; Hopstaken, Rogier; Price, Christopher P; Kusters, Ron; Cals, Jochen W L

2018-01-29

The use of point-of-care tests (POCTs) in family practice is increasing, and the term POCT is often used in medical literature and clinical practice. Yet, no widely supported definition by several professional fields exists. To reach consensus on an international definition of a POCT in family practice. We performed a modified international e-Delphi procedure of four rounds among expert panel members from different professional backgrounds-family practitioners, laboratory specialists, policymakers, researchers and manufacturers. Of 27 panel members from seven different countries, 26 participated in all rounds. Most panel members were active in POCT research or policymaking and 70% worked in family medicine. After choosing important components, structuring of answers and feedback, the following definition was chosen as the best or second best definition by 81% of panel members: a point-of-care test in family practice is a test to support clinical decision making, which is performed by a qualified member of the practice staff nearby the patient and on any part of the patient's body or its derivatives, during or very close to the time of consultation, to help the patient and physician to decide upon the best suited approach, and of which the results should be known at the time of the clinical decision making. The definition emerging from this study can inform family practitioners, laboratory specialists, policymakers and manufacturers on the most widely supported and recognized definition and could act as a clear starting point for the organization and execution of professional point-of-care testing in family practice worldwide. © The Author(s) 2018. Published by Oxford University Press. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

[Joint diagnostic value of four temperature sensation tests in elderly patients with type 2 diabetic peripheral neuropathy].

Science.gov (United States)

Guo, Wei; Li, Yun-Ming; Ai, Zhi-Hua; You, Zhi-Qing; Wan, Yong; Cheng, Ying; Lang, Hong-Mei

2013-07-01

To explore the joint diagnostic value of four temperature sensation tests in elderly patients with type 2 diabetic peripheral neuropathy. Thermal sensory analyzer-II were applied to measure cool sensation (CS), warm sensation (WS), cold pain sensation (CP)and heat pain sensation (HP) of 308 elderly patients with type 2 diabetes. Logistic regression model was adopted to create the new variable Temp4 from four temperature sensation tests to diagnose type 2 diabetic peripheral neuropathy. The ROC curve analysis was used to determine the best cut-off points of the four temperature sensation and Temp4, and the diagnostic value of it was evaluated. The means of temperature sensation tests of the diabetic peripheral neuropathy (DPN) group were significantly different from those of the non-DPN group (P sensation tests to diagnose the DPN, the sensitivity of WS test was the highest, and the value was 0.710; but the specificity, positive predictive value, negative predictive value, Youden index, diagnostic accuracy and Kappa value of cold sensation test were the highest, and the values were 0.842, 0.746, 0.799, 0.528, 77.92% and 0.535, respectively; the Kappa values of the other three temperature sensation tests were all greater than 0.4 (P sensation tests (P sensation quantitative tests were in good agreementand could be applied to diagnose DPN; the new variable Temp4 could be used for diagnosis of DPN with a higher diagnostic accuracy.

Initial field testing definition of subsurface sealing and backfilling tests in unsaturated tuff

International Nuclear Information System (INIS)

Fernandez, J.A.; Case, J.B.; Tyburski, J.R.

1993-05-01

This report contains an initial definition of the field tests proposed for the Yucca Mountain Project repository sealing program. The tests are intended to resolve various performance and emplacement concerns. Examples of concerns to be addressed include achieving selected hydrologic and structural requirements for seals, removing portions of the shaft liner, excavating keyways, emplacing cementitious and earthen seals, reducing the impact of fines on the hydraulic conductivity of fractures, efficient grouting of fracture zones, sealing of exploratory boreholes, and controlling the flow of water by using engineered designs. Ten discrete tests are proposed to address these and other concerns. These tests are divided into two groups: Seal component tests and performance confirmation tests. The seal component tests are thorough small-scale in situ tests, the intermediate-scale borehole seal tests, the fracture grouting tests, the surface backfill tests, and the grouted rock mass tests. The seal system tests are the seepage control tests, the backfill tests, the bulkhead test in the Calico Hills unit, the large-scale shaft seal and shaft fill tests, and the remote borehole sealing tests. The tests are proposed to be performed in six discrete areas, including welded and non-welded environments, primarily located outside the potential repository area. The final selection of sealing tests will depend on the nature of the geologic and hydrologic conditions encountered during the development of the Exploratory Studies Facility and detailed numerical analyses. Tests are likely to be performed both before and after License Application

Review: Diagnostic accuracy of PCR-based detection tests for Helicobacter Pylori in stool samples.

Science.gov (United States)

Khadangi, Fatemeh; Yassi, Maryam; Kerachian, Mohammad Amin

2017-12-01

Although different methods have been established to detect Helicobacter pylori (H. pylori) infection, identifying infected patients is an ongoing challenge. The aim of this meta-analysis was to provide pooled diagnostic accuracy measures for stool PCR test in the diagnosis of H. pylori infection. In this study, a systematic review and meta-analysis were carried out on various sources, including MEDLINE, Web of Sciences, and the Cochrane Library from April 1, 1999, to May 1, 2016. This meta-analysis adheres to the guidelines provided by the Preferred Reporting Items for Systematic Reviews and Meta-Analyses report (PRISMA Statement). The clinical value of DNA stool PCR test was based on the pooled false positive, false negative, true positive, and true negative of different genes. Twenty-six of 328 studies identified met the eligibility criteria. Stool PCR test had a performance of 71% (95% CI: 68-73) sensitivity, 96% (95% CI: 94-97) specificity, and 65.6 (95% CI: 30.2-142.5) diagnostic odds ratio (DOR) in diagnosis of H. pylori. The DOR of genes which showed the highest performance of stool PCR tests was as follows: 23S rRNA 152.5 (95% CI: 55.5-418.9), 16S rRNA 67.9 (95%CI: 6.4-714.3), and glmM 68.1 (95%CI: 20.1-231.7). The sensitivity and specificity of stool PCR test are relatively in the same spectrum of other diagnostic methods for the detection of H. pylori infection. In descending order of significance, the most diagnostic candidate genes using PCR detection were 23S rRNA, 16S rRNA, and glmM. PCR for 23S rRNA gene which has the highest performance could be applicable to detect H. pylori infection. © 2017 John Wiley & Sons Ltd.

Results of metallographical diagnostic examination of Navy half-watt thermoelectric converters degraded by accelerated tests

International Nuclear Information System (INIS)

Rosell, F.E. Jr.; Rouklove, P.G.

1977-01-01

To verify the 15-year reliability of the Navy half-watt radioisotope thermoelectric generator (RTG), bismuth--telluride thermoelectric converters were submitted to testing at high temperatures which accelerated the degradation and caused failure of the converters. Metallographic diagnostic examination of failed units verified failure mechanisms. Results of diagnostic examinations are presented

Beam-Based Diagnostics of RF-Breakdown in the Two-Beam Test-Stand in CTF3

CERN Document Server

Johnson, M

2007-01-01

The general outline of a beam-based diagnostic method of RF-breakdown, using BPMs, at the two-beam test-stand in CTF3 is discussed. The basic components of the set-up and their functions in the diagnostic are described. Estimations of the expected error in the measured parameters are performed.

Estimating the true accuracy of diagnostic tests for dengue infection using bayesian latent class models.

Directory of Open Access Journals (Sweden)

Wirichada Pan-ngum

Full Text Available Accuracy of rapid diagnostic tests for dengue infection has been repeatedly estimated by comparing those tests with reference assays. We hypothesized that those estimates might be inaccurate if the accuracy of the reference assays is not perfect. Here, we investigated this using statistical modeling.Data from a cohort study of 549 patients suspected of dengue infection presenting at Colombo North Teaching Hospital, Ragama, Sri Lanka, that described the application of our reference assay (a combination of Dengue IgM antibody capture ELISA and IgG antibody capture ELISA and of three rapid diagnostic tests (Panbio NS1 antigen, IgM antibody and IgG antibody rapid immunochromatographic cassette tests were re-evaluated using bayesian latent class models (LCMs. The estimated sensitivity and specificity of the reference assay were 62.0% and 99.6%, respectively. Prevalence of dengue infection (24.3%, and sensitivities and specificities of the Panbio NS1 (45.9% and 97.9%, IgM (54.5% and 95.5% and IgG (62.1% and 84.5% estimated by bayesian LCMs were significantly different from those estimated by assuming that the reference assay was perfect. Sensitivity, specificity, PPV and NPV for a combination of NS1, IgM and IgG cassette tests on admission samples were 87.0%, 82.8%, 62.0% and 95.2%, respectively.Our reference assay is an imperfect gold standard. In our setting, the combination of NS1, IgM and IgG rapid diagnostic tests could be used on admission to rule out dengue infection with a high level of accuracy (NPV 95.2%. Further evaluation of rapid diagnostic tests for dengue infection should include the use of appropriate statistical models.

Comparison of a New and Rapid Method: Brucella Coombs Gel Test With Other Diagnostic Tests.

Science.gov (United States)

Kalem, Fatma; Ergün, Ayşe Gül; Durmaz, Süleyman; Doğan, Metin; Ertuğrul, Ömür; Gündem, Seval

2016-09-01

The aim of this study was to detect reliability of Brucella Coombs gel test (BCGT) by comparing with with ELISA (IgG + IgM), Standard agglutination test, and Brucella immunocapture agglutination methods in serological diagnosis of brucellosis. Brucella Coombs gel test (BCGT), Brucella ELISA (IgG + IgM), Standard agglutination test, and Brucella immunocapture agglutination tests of 78 patients with presumptive diagnosis of brucellosis which were sent to Microbiology Laboratory of Konya Numune Hospital from various regions of Konya were studied. Of 78 patients with ELISA IgG and IgM, STA, BICA and BCGT; 26, 21, 10, 12 and 12 were positive. When compared with BICA, the sensitivity and specifity of BCGT were 100% and 100%, respectively. According to results BCGT can be used as a diagnostic test in routine laboratories after more comprehensive studies in control groups and patients. © 2016 Wiley Periodicals, Inc.

COPD: Definition and Phenotypes

DEFF Research Database (Denmark)

Vestbo, J.

2014-01-01

particles or gases. Exacerbations and comorbidities contribute to the overall severity in individual patients. The evolution of this definition and the diagnostic criteria currently in use are discussed. COPD is increasingly divided in subgroups or phenotypes based on specific features and association...

[Diagnostic capacity of skin prick test in egg and cow's milk allergic infants].

Science.gov (United States)

Yan, Jun-mei; Chen, Jing; Li, Hai-qi; Hu, Yan

2011-05-01

Mean diameter is the most common used parameter for wheal response assessment after skin prick test. This study aimed to investigate the diagnostic capacity of mean diameter according to the outcome of oral food challenge, and to determine the cut-off points that could render food challenges unnecessary. Data of 173 children referred to the Division of Primary Child Health Care for the evaluation of suspected food allergy were prospectively studied. All children underwent skin prick test and open food challenge to the relevant food(s) in clinic. The mean wheal diameter of skin prick test was measured, and open food challenge was performed to confirm food allergy. The SPSS software package version 13.0 for windows (SPSS, Chicago, IL, USA) was used for all statistical analysis. Open food challenge was taken as the gold standard for diagnosis. Diagnostic capacity of skin prick test, including the sensitivity, specificity, positive predictive value, negative predictive value, was calculated by cross-table. In addition, receiver operating characteristic curve (ROC) was plotted and area under the curve (AUC) was calculated to quantify the accuracy of the parameter. For the 173 children, 271 open food challenges were performed with egg white, egg yolk and cow's milk, In which 123 were positive, 99 children were diagnosed as food allergy. Cutaneous symptoms (87.0%) were most common, followed by gastrointestinal symptoms (9.8%). The AUC of mean diameter was 0.794 for egg white, 0.804 for egg yolk and 0.904 for cow's milk. The sensitivity of skin prick test with a cut-off value of ≥ 3 mm was ranged from 71% to 87%, while the specificity was between 31% and 57%. The authors also defined food specific skin prick test mean diameters that were 100% diagnostic for allergy to egg white (≥ 8.5 mm), egg yolk (≥ 5.5 mm), cow's milk (≥ 5.5 mm). Predictive decision points for a positive outcome of food challenges can be calculated for egg and cow's milk using mean diameter. It

Uncertainty during breast diagnostic evaluation: state of the science.

Science.gov (United States)

Montgomery, Mariann

2010-01-01

To present the state of the science on uncertainty in relationship to the experiences of women undergoing diagnostic evaluation for suspected breast cancer. Published articles from Medline, CINAHL, PubMED, and PsycINFO from 1983-2008 using the following key words: breast biopsy, mammography, uncertainty, reframing, inner strength, and disruption. Fifty research studies were examined with all reporting the presence of anxiety persisting throughout the diagnostic evaluation until certitude is achieved through the establishment of a definitive diagnosis. Indirect determinants of uncertainty for women undergoing breast diagnostic evaluation include measures of anxiety, depression, social support, emotional responses, defense mechanisms, and the psychological impact of events. Understanding and influencing the uncertainty experience have been suggested to be key in relieving psychosocial distress and positively influencing future screening behaviors. Several studies examine correlational relationships among anxiety, selection of coping methods, and demographic factors that influence uncertainty. A gap exists in the literature with regard to the relationship of inner strength and uncertainty. Nurses can be invaluable in assisting women in coping with the uncertainty experience by providing positive communication and support. Nursing interventions should be designed and tested for their effects on uncertainty experienced by women undergoing a breast diagnostic evaluation.

Aminopenicillin-associated exanthem: lymphocyte transformation testing revisited.

Science.gov (United States)

Trautmann, A; Seitz, C S; Stoevesandt, J; Kerstan, A

2014-12-01

The lymphocyte transformation test (LTT) has been promoted as in-vitro test for diagnosis of drug hypersensitivity. For determination of statistical LTT sensitivity, series of patients with clinically uniform reactions followed by complete drug hypersensitivity work-up are mandatory. Assessment of LTT specificity requires control patients who tolerated exposure to the drug studied. To prospectively determine the diagnostic value of the LTT in a clinically and diagnostically well-defined series of patients. Patients with exanthematous skin eruptions after ampicillin (AMP) intake were included in this study. After exclusion or confirmation of delayed-onset allergic AMP hypersensitivity by skin and provocation testing, two independent LTTs were performed: one standard LTT and a modified LTT with additional anti-CD3/anti-CD28 monoclonal antibody stimulation. By testing, delayed-onset allergic AMP hypersensitivity was diagnosed in 11 patients and definitely ruled out in 26. The standard LTT reached a diagnostic sensitivity of 54.5% while the modified LTT yielded 72.7%. However, the methodical test modification resulted in a decline of specificity from 92.3% (standard LTT) to 76.9%. In cases of AMP-associated exanthems, the diagnostic value of the LTT compared with routine allergy testing is limited. When evaluating such exanthems, provocation testing remains the gold standard. Delayed reading of intradermal skin tests remains most useful to avoid positive provocation reactions. © 2014 John Wiley & Sons Ltd.

Diagnostic efficacy of in vitro methods vs. skin testing in patients with inhalant allergies

International Nuclear Information System (INIS)

Corey, J.P.; Liudahl, J.J.; Young, S.A.; Rodman, S.M.

1991-01-01

The purpose of our study was to investigate the diagnostic efficacy of two selected methods of in vitro allergy testing. Specifically, the PRIST/modified RAST I125 isotope systems and the Quantizyme/modified EAST alkaline phosphatase method were compared. The time, expense, convenience, and diagnostic efficacy of the two procedures are discussed. Special attention is given to the practicality of each method for the practicing physician

Single and Combined Diagnostic Value of Clinical Features and Laboratory Tests in Acute Appendicitis

NARCIS (Netherlands)

Laméris, Wytze; van Randen, Adrienne; Go, Peter M. N. Y. H.; Bouma, Wim H.; Donkervoort, Sandra C.; Bossuyt, Patrick M. M.; Stoker, Jaap; Boermeester, Marja A.

2009-01-01

Objectives: The objective was to evaluate the diagnostic accuracy of clinical features and laboratory test results in detecting acute appendicitis. Methods: Clinical features and laboratory test results were prospectively recorded in a consecutive series of 1,101 patients presenting with abdominal

Diagnostic Accuracy of Molecular Amplification Tests for Human African Trypanosomiasis-Systematic Review

NARCIS (Netherlands)

Mugasa, Claire M.; Adams, Emily R.; Boer, Kimberly R.; Dyserinck, Heleen C.; Büscher, Philippe; Schallig, Henk D. H. F.; Leeflang, Mariska M. G.

2012-01-01

Background: A range of molecular amplification techniques have been developed for the diagnosis of Human African Trypanosomiasis (HAT); however, careful evaluation of these tests must precede implementation to ensure their high clinical accuracy. Here, we investigated the diagnostic accuracy of

Urinary tract infections in general practice patients: diagnostic tests versus bacteriological culture.

NARCIS (Netherlands)

Nys, S.; Merode, T. van; Bartelds, A.I.M.; Stobberingh, E.E.

2006-01-01

Objectives: Urinary tract infections (UTIs) are common bacterial infections encountered in general practice. For the optimal treatment the general practitioner (GP) should rely on the results of diagnostic tests and recent antimicrobial susceptibility of uropathogens. Patients and methods: In total

Remote visual testing (RVT) for the diagnostic inspection of feedwater heaters

International Nuclear Information System (INIS)

Nugent, M.J.; Pellegrino, B.A.

1991-01-01

In this paper the benefits and limitations of Non-Destructive Testing (NDT) on feedwater heaters will be briefly reviewed. All Remote Visual Testing (RVT) devices including borescopes, fiberscopes, videoborescopes and Closed Circuit Television (CCTV) cameras will be discussed along with currently accepted formats for documentation. The benefits of a comprehensive in-place inspection involving Remote Visual Testing will be discussed in relationship to its diagnostic capabilities. The results of eight post-service heater inspections will be discussed along with the root cause of failure of seven unique failure mechanisms. These inspections, including FWH access, RVT tool and data analysis, will be detailed

Diagnostic validation of three test methods for detection of cyprinid herpesvirus 3 (CyHV-3).

Science.gov (United States)

Clouthier, Sharon C; McClure, Carol; Schroeder, Tamara; Desai, Megan; Hawley, Laura; Khatkar, Sunita; Lindsay, Melissa; Lowe, Geoff; Richard, Jon; Anderson, Eric D

2017-03-06

Cyprinid herpesvirus 3 (CyHV-3) is the aetiological agent of koi herpesvirus disease in koi and common carp. The disease is notifiable to the World Organisation for Animal Health. Three tests-quantitative polymerase chain reaction (qPCR), conventional PCR (cPCR) and virus isolation by cell culture (VI)-were validated to assess their fitness as diagnostic tools for detection of CyHV-3. Test performance metrics of diagnostic accuracy were sensitivity (DSe) and specificity (DSp). Repeatability and reproducibility were measured to assess diagnostic precision. Estimates of test accuracy, in the absence of a gold standard reference test, were generated using latent class models. Test samples originated from wild common carp naturally exposed to CyHV-3 or domesticated koi either virus free or experimentally infected with the virus. Three laboratories in Canada participated in the precision study. Moderate to high repeatability (81 to 99%) and reproducibility (72 to 97%) were observed for the qPCR and cPCR tests. The lack of agreement observed between some of the PCR test pair results was attributed to cross-contamination of samples with CyHV-3 nucleic acid. Accuracy estimates for the PCR tests were 99% for DSe and 93% for DSp. Poor precision was observed for the VI test (4 to 95%). Accuracy estimates for VI/qPCR were 90% for DSe and 88% for DSp. Collectively, the results show that the CyHV-3 qPCR test is a suitable tool for surveillance, presumptive diagnosis and certification of individuals or populations as CyHV-3 free.

Development and testing of a diagnostic system for intelligen distributed control at EBR-2

International Nuclear Information System (INIS)

Edwards, R.M.; Ruhl, D.W.; Klevans, E.H.; Robinson, G.E.

1990-01-01

A diagnostic system is under development for demonstration of Intelligent Distributed Control at the Experimental Breeder Reactor (EBR--II). In the first phase of the project a diagnostic system is being developed for the EBR-II steam plant based on the DISYS expert systems approach. Current testing uses recorded plant data and data from simulated plant faults. The dynamical simulation of the EBR-II steam plant uses the Babcock and Wilcox (B ampersand W) Modular Modeling System (MMS). At EBR-II the diagnostic system operates in the UNIX workstation and receives live plant data from the plant Data Acquisition System (DAS). Future work will seek implementation of the steam plant diagnostic in a distributed manner using UNIX based computers and Bailey microprocessor-based control system. 10 refs., 6 figs

9 CFR 130.17 - User fees for other veterinary diagnostic laboratory tests performed at NVSL (excluding FADDL) or...

Science.gov (United States)

2010-01-01

... 9 Animals and Animal Products 1 2010-01-01 2010-01-01 false User fees for other veterinary... FEES USER FEES § 130.17 User fees for other veterinary diagnostic laboratory tests performed at NVSL (excluding FADDL) or at authorized sites. (a) User fees for veterinary diagnostics tests performed at the...

9 CFR 130.16 - User fees for veterinary diagnostic serology tests performed at NVSL (excluding FADDL) or at...

Science.gov (United States)

2010-01-01

... 9 Animals and Animal Products 1 2010-01-01 2010-01-01 false User fees for veterinary diagnostic serology tests performed at NVSL (excluding FADDL) or at authorized sites. 130.16 Section 130.16 Animals... USER FEES § 130.16 User fees for veterinary diagnostic serology tests performed at NVSL (excluding...

A Review of Neuropathic Pain: From Diagnostic Tests to Mechanisms

OpenAIRE

Truini, Andrea

2017-01-01

Neuropathic pain develops when the somatosensory nervous system is affected by a lesion or disease. Diagnostic tests aimed at assessing somatosensory afferent pathway damage are therefore useful for diagnosing neuropathic pain. Neuropathic pain manifests with a range of different symptoms such as ongoing burning pain, squeezing or pressure pain, paroxysmal electric shock-like sensations, stabbing pain, or mechanical dynamic allodynia. The various types of neuropathic pain are associated with ...

Diagnostic Accuracy of Quantitative Sensory Testing to Discriminate Inflammatory Toothache and Intraoral Neuropathic Pain.

Science.gov (United States)

Porporatti, André Luís; Costa, Yuri Martins; Stuginski-Barbosa, Juliana; Bonjardim, Leonardo Rigoldi; Duarte, Marco Antônio Hungaro; Conti, Paulo César Rodrigues

2015-10-01

A differential diagnosis between inflammatory toothache (IT) and intraoral neuropathic pain is challenging. The aim of this diagnostic study was to quantify somatosensory function of subjects with IT (acute pulpitis) and atypical odontalgia (AO, intraoral neuropathic pain) and healthy volunteers and to quantify how accurately quantitative sensory testing (QST) discriminates an IT or AO diagnosis. The sample consisted of 60 subjects equally divided (n = 20) into 3 groups: (1) IT, (2) AO, and (3) control. A sequence of 4 QST methods was performed over the dentoalveolar mucosa in the apical maxillar or mandibular area: mechanical detection threshold, pain detection threshold (PDT), dynamic mechanical allodynia, and temporal summation. One-way analysis of variance, Tukey post hoc analyses, and z score transformation were applied to the data. In addition, the receiver operating characteristic curve analysis, diagnostic accuracy, sensitivity, specificity, likelihood ratios, and diagnostic odds ratio of the QST methods were calculated (α = 5%). Somatosensory abnormalities were found for the AO group, which is consistent with a low detection threshold to touch and pain and the presence of mechanical allodynia. For the IT group, no somatosensory abnormality was observed when compared with the control group. The most accurate QST to discriminate the diagnostic differences between IT and healthy individuals is the PDT. The diagnostic differences between AO and healthy individuals and between IT and AO are best discriminated with the mechanical detection threshold, PDT, and dynamic mechanical allodynia. The proposed QST methods may aid in the differential diagnosis between IT and AO with strong accuracy and may be used as complementary diagnostic tests. Copyright © 2015 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.

A diagnostic model incorporating P50 sensory gating and neuropsychological tests for schizophrenia.

Directory of Open Access Journals (Sweden)

Jia-Chi Shan

Full Text Available OBJECTIVES: Endophenotypes in schizophrenia research is a contemporary approach to studying this heterogeneous mental illness, and several candidate neurophysiological markers (e.g. P50 sensory gating and neuropsychological tests (e.g. Continuous Performance Test (CPT and Wisconsin Card Sorting Test (WCST have been proposed. However, the clinical utility of a single marker appears to be limited. In the present study, we aimed to construct a diagnostic model incorporating P50 sensory gating with other neuropsychological tests in order to improve the clinical utility. METHODS: We recruited clinically stable outpatients meeting DSM-IV criteria of schizophrenia and age- and gender-matched healthy controls. Participants underwent P50 sensory gating experimental sessions and batteries of neuropsychological tests, including CPT, WCST and Wechsler Adult Intelligence Scale Third Edition (WAIS-III. RESULTS: A total of 106 schizophrenia patients and 74 healthy controls were enrolled. Compared with healthy controls, the patient group had significantly a larger S2 amplitude, and thus poorer P50 gating ratio (gating ratio = S2/S1. In addition, schizophrenia patients had a poorer performance on neuropsychological tests. We then developed a diagnostic model by using multivariable logistic regression analysis to differentiate patients from healthy controls. The final model included the following covariates: abnormal P50 gating (defined as P50 gating ratio >0.4, three subscales derived from the WAIS-III (Arithmetic, Block Design, and Performance IQ, sensitivity index from CPT and smoking status. This model had an adequate accuracy (concordant percentage = 90.4%; c-statistic = 0.904; Hosmer-Lemeshow Goodness-of-Fit Test, p = 0.64>0.05. CONCLUSION: To the best of our knowledge, this is the largest study to date using P50 sensory gating in subjects of Chinese ethnicity and the first to use P50 sensory gating along with other neuropsychological tests

Diagnostic test accuracy of nutritional tools used to identify undernutrition in patients with colorectal cancer: a systematic review.

Science.gov (United States)

Håkonsen, Sasja Jul; Pedersen, Preben Ulrich; Bath-Hextall, Fiona; Kirkpatrick, Pamela

2015-05-15

Effective nutritional screening, nutritional care planning and nutritional support are essential in all settings, and there is no doubt that a health service seeking to increase safety and clinical effectiveness must take nutritional care seriously. Screening and early detection of malnutrition is crucial in identifying patients at nutritional risk. There is a high prevalence of malnutrition in hospitalized patients undergoing treatment for colorectal cancer. To synthesize the best available evidence regarding the diagnostic test accuracy of nutritional tools (sensitivity and specificity) used to identify malnutrition (specifically undernutrition) in patients with colorectal cancer (such as the Malnutrition Screening Tool and Nutritional Risk Index) compared to reference tests (such as the Subjective Global Assessment or Patient Generated Subjective Global Assessment). Patients with colorectal cancer requiring either (or all) surgery, chemotherapy and/or radiotherapy in secondary care. Focus of the review: The diagnostic test accuracy of validated assessment tools/instruments (such as the Malnutrition Screening Tool and Nutritional Risk Index) in the diagnosis of malnutrition (specifically under-nutrition) in patients with colorectal cancer, relative to reference tests (Subjective Global Assessment or Patient Generated Subjective Global Assessment). Types of studies: Diagnostic test accuracy studies regardless of study design. Studies published in English, German, Danish, Swedish and Norwegian were considered for inclusion in this review. Databases were searched from their inception to April 2014. Methodological quality was determined using the Quality Assessment of Diagnostic Accuracy Studies checklist. Data was collected using the data extraction form: the Standards for Reporting Studies of Diagnostic Accuracy checklist for the reporting of studies of diagnostic accuracy. The accuracy of diagnostic tests is presented in terms of sensitivity, specificity, positive

Preliminary project definition for long duration. Tests of coal fired MHD generators

International Nuclear Information System (INIS)

Van der Laken, R.A.

1992-01-01

In its final report the Faraday Working Group recommended the CEC amongst others to explore the possibility of a long duration test of a 'state-of-the-art', MHD-generator in order to remove uncertainties concerning the lifetime and availability of such a generator design. The duration of the test should be several thousands of hours, considerably more than the duration tests carried out until now. The scope of the present study is to prepare a project definition document for a long duration test of a coal fired, state-of-the-art MHD-generator

Issues in the definition and diagnosis of alcoholism: implications for a reformulation.

Science.gov (United States)

Babor, T F; Kranzler, H R; Kadden, R M

1986-01-01

This paper examines definitions of alcoholism from theoretical and historical points of view. It begins with a review of definitions of alcoholism from the 19th century to the present, giving particular attention to medical approaches, psychiatric formulations, behavioral concepts, and definitions proposed by the American Psychiatric Association and the World Health Organization. It is concluded that current definitions differ widely in scope, the meanings attached to words like disease and disorder, the criteria for including signs and symptoms as essential characteristics, and the potential uses of the definitions. Based on these considerations, the practical issues of developing and applying clinically useful diagnostic procedures are discussed. The paper concludes with a discussion of diagnostic issues that should be considered in any effort to improve clinical identification, treatment planning and international communication.

Estimation of Cachexia among Cancer Patients Based on Four Definitions

Directory of Open Access Journals (Sweden)

Kathleen M. Fox

2009-01-01

Full Text Available Objectives. Estimate and compare the proportion of cancer patients with cachexia using different definitions from available clinical data. Methods. Electronic medical records were examined to estimate the proportion of cancer patients with cachexia using 4 definitions: (1 ICD-9 diagnostic code of 799.4 (cachexia, (2 ICD-9 diagnosis of cachexia, anorexia, abnormal weight loss, or feeding difficulties, (3 prescription for megestrol acetate, oxandrolone, somatropin, or dronabinol, and (4 ≥5% weight loss. Patients with cancer of the stomach, pancreas, lung, colon/rectum, head/neck, esophagus, prostate, breast, or liver diagnosed between 1999 and 2004 were followed for cachexia. Results. Of 8541 cancer patients (60% men and 55% Caucasian, cachexia was observed in 2.4% of patients using the cachexia diagnostic code, 5.5% expanded diagnoses, 6.4% prescription medication definition, and 14.7% with ≥5% weight loss. Conclusions. The proportion of patients with cachexia varied considerably depending upon the definition employed, indicating that a standard operational definition is needed.

The meaning of diagnostic test results: A spreadsheet for swift data analysis

International Nuclear Information System (INIS)

MacEneaney, Peter M.; Malone, Dermot E.

2000-01-01

AIMS: To design a spreadsheet program to: (a) analyse rapidly diagnostic test result data produced in local research or reported in the literature; (b) correct reported predictive values for disease prevalence in any population; (c) estimate the post-test probability of disease in individual patients. MATERIALS AND METHODS: Microsoft Excel TM was used. Section A: a contingency (2 x 2) table was incorporated into the spreadsheet. Formulae for standard calculations [sample size, disease prevalence, sensitivity and specificity with 95% confidence intervals, predictive values and likelihood ratios (LRs)] were linked to this table. The results change automatically when the data in the true or false negative and positive cells are changed. Section B: this estimates predictive values in any population, compensating for altered disease prevalence. Sections C-F: Bayes' theorem was incorporated to generate individual post-test probabilities. The spreadsheet generates 95% confidence intervals, LRs and a table and graph of conditional probabilities once the sensitivity and specificity of the test are entered. The latter shows the expected post-test probability of disease for any pre-test probability when a test of known sensitivity and specificity is positive or negative. RESULTS: This spreadsheet can be used on desktop and palmtop computers. The MS Excel TM version can be downloaded via the Internet from the URL ftp://radiography.com/pub/Rad-data99.xls CONCLUSION: A spreadsheet is useful for contingency table data analysis and assessment of the clinical meaning of diagnostic test results. MacEneaney, P.M., Malone, D.E. (2000)

Infection with Pathogens Transmitted Commonly Through Food and the Effect of Increasing Use of Culture-Independent Diagnostic Tests on Surveillance--Foodborne Diseases Active Surveillance Network, 10 U.S. Sites, 2012-2015.

Science.gov (United States)

Huang, Jennifer Y; Henao, Olga L; Griffin, Patricia M; Vugia, Duc J; Cronquist, Alicia B; Hurd, Sharon; Tobin-D'Angelo, Melissa; Ryan, Patricia; Smith, Kirk; Lathrop, Sarah; Zansky, Shelley; Cieslak, Paul R; Dunn, John; Holt, Kristin G; Wolpert, Beverly J; Patrick, Mary E

2016-04-15

To evaluate progress toward prevention of enteric and foodborne illnesses in the United States, the Foodborne Diseases Active Surveillance Network (FoodNet) monitors the incidence of laboratory-confirmed infections caused by nine pathogens transmitted commonly through food in 10 U.S. sites. This report summarizes preliminary 2015 data and describes trends since 2012. In 2015, FoodNet reported 20,107 confirmed cases (defined as culture-confirmed bacterial infections and laboratory-confirmed parasitic infections), 4,531 hospitalizations, and 77 deaths. FoodNet also received reports of 3,112 positive culture-independent diagnostic tests (CIDTs) without culture-confirmation, a number that has markedly increased since 2012. Diagnostic testing practices for enteric pathogens are rapidly moving away from culture-based methods. The continued shift from culture-based methods to CIDTs that do not produce the isolates needed to distinguish between strains and subtypes affects the interpretation of public health surveillance data and ability to monitor progress toward prevention efforts. Expanded case definitions and strategies for obtaining bacterial isolates are crucial during this transition period.

Reactor protection system with automatic self-testing and diagnostic

International Nuclear Information System (INIS)

Gaubatz, D.C.

1996-01-01

A reactor protection system is disclosed having four divisions, with quad redundant sensors for each scram parameter providing input to four independent microprocessor-based electronic chassis. Each electronic chassis acquires the scram parameter data from its own sensor, digitizes the information, and then transmits the sensor reading to the other three electronic chassis via optical fibers. To increase system availability and reduce false scrams, the reactor protection system employs two levels of voting on a need for reactor scram. The electronic chassis perform software divisional data processing, vote 2/3 with spare based upon information from all four sensors, and send the divisional scram signals to the hardware logic panel, which performs a 2/4 division vote on whether or not to initiate a reactor scram. Each chassis makes a divisional scram decision based on data from all sensors. Automatic detection and discrimination against failed sensors allows the reactor protection system to automatically enter a known state when sensor failures occur. Cross communication of sensor readings allows comparison of four theoretically ''identical'' values. This permits identification of sensor errors such as drift or malfunction. A diagnostic request for service is issued for errant sensor data. Automated self test and diagnostic monitoring, sensor input through output relay logic, virtually eliminate the need for manual surveillance testing. This provides an ability for each division to cross-check all divisions and to sense failures of the hardware logic. 16 figs

Safety and Yield of Diagnostic ERCP in Liver Transplant Patients with Abnormal Liver Function Tests

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Jayapal Ramesh

2014-01-01

Full Text Available Background. Abnormal liver enzymes postorthotopic liver transplant (OLT may indicate significant biliary pathology or organ rejection. There is very little known in the literature regarding the current role of diagnostic ERCP in this scenario. Aim. To review the utility of diagnostic ERCP in patients presenting with abnormal liver function tests in the setting of OLT. Methods. A retrospective review of diagnostic ERCPs in patients with OLT from 2002 to 2013 from a prospectively maintained, IRB approved database. Results. Of the 474 ERCPs performed in OLT patients, 210 (44.3%; 95% CI 39.8–48.8 were performed for abnormal liver function tests during the study period. Majority of patients were Caucasian (83.8%, male (62.4% with median age of 55 years (IQR 48–62 years. Biliary cannulation was successful in 99.6% of cases and findings included stricture in 45 (21.4 %; biliary stones/sludge in 23 (11%; biliary dilation alone in 31 (14.8%; and normal in 91 (43.3%. Three (1.4% patients developed mild, self-limiting pancreatitis; one patient (0.5% developed cholangitis and two (1% had postsphincterotomy bleeding. Multivariate analyses showed significant association between dilated ducts on imaging with a therapeutic outcome. Conclusion. Diagnostic ERCP in OLT patients presenting with liver function test abnormalities is safe and frequently therapeutic.

HIV misdiagnosis in sub-Saharan Africa: performance of diagnostic algorithms at six testing sites

Science.gov (United States)

Kosack, Cara S.; Shanks, Leslie; Beelaert, Greet; Benson, Tumwesigye; Savane, Aboubacar; Ng’ang’a, Anne; Andre, Bita; Zahinda, Jean-Paul BN; Fransen, Katrien; Page, Anne-Laure

2017-01-01

Abstract Introduction: We evaluated the diagnostic accuracy of HIV testing algorithms at six programmes in five sub-Saharan African countries. Methods: In this prospective multisite diagnostic evaluation study (Conakry, Guinea; Kitgum, Uganda; Arua, Uganda; Homa Bay, Kenya; Doula, Cameroun and Baraka, Democratic Republic of Congo), samples from clients (greater than equal to five years of age) testing for HIV were collected and compared to a state-of-the-art algorithm from the AIDS reference laboratory at the Institute of Tropical Medicine, Belgium. The reference algorithm consisted of an enzyme-linked immuno-sorbent assay, a line-immunoassay, a single antigen-enzyme immunoassay and a DNA polymerase chain reaction test. Results: Between August 2011 and January 2015, over 14,000 clients were tested for HIV at 6 HIV counselling and testing sites. Of those, 2786 (median age: 30; 38.1% males) were included in the study. Sensitivity of the testing algorithms ranged from 89.5% in Arua to 100% in Douala and Conakry, while specificity ranged from 98.3% in Doula to 100% in Conakry. Overall, 24 (0.9%) clients, and as many as 8 per site (1.7%), were misdiagnosed, with 16 false-positive and 8 false-negative results. Six false-negative specimens were retested with the on-site algorithm on the same sample and were found to be positive. Conversely, 13 false-positive specimens were retested: 8 remained false-positive with the on-site algorithm. Conclusions: The performance of algorithms at several sites failed to meet expectations and thresholds set by the World Health Organization, with unacceptably high rates of false results. Alongside the careful selection of rapid diagnostic tests and the validation of algorithms, strictly observing correct procedures can reduce the risk of false results. In the meantime, to identify false-positive diagnoses at initial testing, patients should be retested upon initiating antiretroviral therapy. PMID:28691437

Bias in logistic regression due to imperfect diagnostic test results and practical correction approaches.

Science.gov (United States)

Valle, Denis; Lima, Joanna M Tucker; Millar, Justin; Amratia, Punam; Haque, Ubydul

2015-11-04

Logistic regression is a statistical model widely used in cross-sectional and cohort studies to identify and quantify the effects of potential disease risk factors. However, the impact of imperfect tests on adjusted odds ratios (and thus on the identification of risk factors) is under-appreciated. The purpose of this article is to draw attention to the problem associated with modelling imperfect diagnostic tests, and propose simple Bayesian models to adequately address this issue. A systematic literature review was conducted to determine the proportion of malaria studies that appropriately accounted for false-negatives/false-positives in a logistic regression setting. Inference from the standard logistic regression was also compared with that from three proposed Bayesian models using simulations and malaria data from the western Brazilian Amazon. A systematic literature review suggests that malaria epidemiologists are largely unaware of the problem of using logistic regression to model imperfect diagnostic test results. Simulation results reveal that statistical inference can be substantially improved when using the proposed Bayesian models versus the standard logistic regression. Finally, analysis of original malaria data with one of the proposed Bayesian models reveals that microscopy sensitivity is strongly influenced by how long people have lived in the study region, and an important risk factor (i.e., participation in forest extractivism) is identified that would have been missed by standard logistic regression. Given the numerous diagnostic methods employed by malaria researchers and the ubiquitous use of logistic regression to model the results of these diagnostic tests, this paper provides critical guidelines to improve data analysis practice in the presence of misclassification error. Easy-to-use code that can be readily adapted to WinBUGS is provided, enabling straightforward implementation of the proposed Bayesian models.

The Value of Naproxen Test as a Diagnostic Method to Differentiate Cause of Fever

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Omer Coskun

2012-12-01

Full Text Available Objective: Fever of whatever etiology still remains a perplexing problem to both clinicians and investigators. Increasingly, its role in connective tissue diseases, malignancies and other inflammatory disorders is slowly supplanting the exclusivity of the symptom to just infectious conditions. This study aims to determine the sensitivity of the naproxen test and the diagnostic value in patients with a prolonged febrile illness. Methods: We evaluated twenty patients had been administered the naproxen test. Fever lysis after or within the time frame of drug administration was interpreted as a infectious or an infectious condition. Results: Infectious diseases etiology was detected at 15 patients. 12 and 3 of them responded to naproxen test at the first and second days respectively. Two of non-infectious etiology patients remained unanswered. Conclusion: This study clearly showed that the naproxen test cannot be relied upon to guide diagnostic decision making in patients with fever unknown origin. [TAF Prev Med Bull 2012; 11(6.000: 779-782

Diagnostic evaluation of rapid tests for scrub typhus in the Indian population is needed.

Science.gov (United States)

Shivalli, Siddharudha

2016-05-12

Owing to frequent outbreaks witnessed in different parts of the country in the recent past, scrub typhus is being described as a re-emerging infectious disease in India. Differentiating scrub typhus from other endemic diseases like malaria, leptospirosis, dengue fever, typhoid, etc. is difficult due to overlapping clinical features and a lower positivity for eschars in Asian populations. Hence, the diagnosis heavily relies on laboratory tests. Costs and the need of technical expertise limit the wide use of indirect immunoperoxidase or immunofluorescence assays, ELISA and PCR. The Weil-Felix test is the most commonly used and least expensive serological test, but lacks both sensitivity and specificity. Hence, the diagnosis of scrub typhus is often delayed or overlooked. With due consideration of the cost, rapidity, single test result and simplicity of interpretation, rapid diagnostic tests have come into vogue. However, evaluation of rapid diagnostic tests for scrub typhus in the Indian population is needed to justify or discourage their use. Research studies are needed to find the most suitable test in terms of the rapidity of the result, simplicity of the procedure, ease of interpretation and cost to be used in the Indian populace.

9 CFR 130.15 - User fees for veterinary diagnostic isolation and identification tests performed at NVSL...

Science.gov (United States)

2010-01-01

... 9 Animals and Animal Products 1 2010-01-01 2010-01-01 false User fees for veterinary diagnostic isolation and identification tests performed at NVSL (excluding FADDL) or other authorized site. 130.15... AGRICULTURE USER FEES USER FEES § 130.15 User fees for veterinary diagnostic isolation and identification...

Utilisation du test GeneXpert pour le diagnostic de la tuberculose au ...

African Journals Online (AJOL)

Utilisation du test GeneXpert pour le diagnostic de la tuberculose au service des maladies infectieuses du CHNU de Fann. Sylvie Audrey Diop, Aminata Massaly, Daye Ka, Noel Magloire Manga, Louise Fortes-Déguénonvo, Cheikh Tidiane Ndour, Viviane Marie Pierre Cisse, Moussa Seydi ...

Mathematics Diagnostic Testing in Engineering: An International Comparison between Ireland and Portugal

Science.gov (United States)

Carr, M.; Fidalgo, C.; Bigotte de Almeida, M. E.; Branco, J. R.; Santos, V.; Murphy, E.; Ní Fhloinn, E.

2015-01-01

Concern has been expressed throughout Europe about the significant deficiencies in the basic mathematical skills of many engineering undergraduates. Mathematics diagnostic tests in the UK, Ireland and Portugal have shown these shortcomings, which provide a challenge to those striving to introduce more innovative educational practices into…

A Comparison of Salivary Steroid Levels during Diagnostic Tests for Adrenal Insufficiency

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Michaela Dušková

2016-01-01

Full Text Available Numerous diagnostic tests are used to evaluate the hypothalamic-pituitary-adrenal axis (HPA axis. The gold standard is still considered the insulin tolerance test (ITT, but this test has many limitations. Current guidelines therefore recommend the Synacthen test first when an HPA axis insufficiency is suspected. However, the dose of Synacthen that is diagnostically most accurate and sensitive is still a matter of debate. We investigated 15 healthy men with mean/median age 27.4/26 (SD ±4.8 years, and mean/median BMI (body mass index 25.38/24.82 (SD ±3.2 kg/m2. All subjects underwent 4 dynamic tests of the HPA axis, specifically 1 μg, 10 μg, and 250 μg Synacthen (ACTH tests and an ITT. Salivary cortisol, cortisone, pregnenolone, and DHEA (dehydroepiandrosterone were analysed using liquid chromatography-tandem mass spectrometry. During the ITT maximum salivary cortisol levels over 12.5 nmol/l were found at 60 minutes. Maximum cortisol levels in all of the Synacthen tests were higher than this; however, demonstrating that sufficient stimulation of the adrenal glands was achieved. Cortisone reacted similarly as cortisol, i.e. we did not find any change in the ratio of cortisol to cortisone. Pregnenolone and DHEA were higher during the ITT, and their peaks preceded the cortisol peak. There was no increase of pregnenolone or DHEA in any of the Synacthen tests. We demonstrate that the 10 μg Synacthen dose is sufficient stimulus for testing the HPA axis and is also a safe and cost-effective alternative. This dose also largely eliminates both false negative and false positive results.

Performance and Pain Tolerability of Current Diagnostic Allergy Skin Prick Test Devices.

Science.gov (United States)

Tversky, Jody R; Chelladurai, Yohalakshmi; McGready, John; Hamilton, Robert G

2015-01-01

Allergen skin prick testing remains an essential tool for diagnosing atopic disease and guiding treatment. Sensitivity needs to be defined for newly introduced devices. Our aim was to compare the performance of 10 current allergy skin prick test devices. Single- and multiheaded skin test devices (n = 10) were applied by a single operator in a prospective randomized manner. Histamine (1 and 6 mg/mL) and control diluent were introduced at 6 randomized locations onto the upper and lower arms of healthy subjects. Wheal and flare reactions were measured independently by 2 masked technicians. Twenty-four subjects provided consent, and 768 skin tests were placed. Mean wheal diameter among devices differed from 3.0 mm (ComforTen; Hollister-Stier, Spokane, Wash) to 6.8 mm (UniTest PC; Lincoln Diagnostics, Decatur, Ill) using 1 mg/mL histamine (P Diagnostics, Decatur, Ill; and Sharp-Test; Panatrex, Placentia, Calif) using 6 mg/mL histamine (P pain score of less than 4 on a 10-point visual analog scale. Pain scores were higher among women, but this did not reach statistical significance. The Multi-Test PC and the UniTest PC had the lowest pain scores compared with the other devices. All 10 skin prick test devices displayed good analytical sensitivity and specificity; however, 3 mm cannot arbitrarily be used as a positive threshold. The use of histamine at 1 mg/mL is unacceptable for certain devices but may be preferable for the most sensitive devices. On average, there was no pain score difference between multiheaded and single-head devices. Copyright © 2015 American Academy of Allergy, Asthma & Immunology. Published by Elsevier Inc. All rights reserved.

The Hug-up Test: A New, Sensitive Diagnostic Test for Supraspinatus Tears

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Yu-Lei Liu

2016-01-01

Full Text Available Background: The supraspinatus tendon is the most commonly affected tendon in rotator cuff tears. Early detection of a supraspinatus tear using an accurate physical examination is, therefore, important. However, the currently used physical tests for detecting supraspinatus tears are poor diagnostic indicators and involve a wide range of sensitivity and specificity values. Therefore, the aim of this study was to establish a new physical test for the diagnosis of supraspinatus tears and evaluate its accuracy in comparison with conventional tests. Methods: Between November 2012 and January 2014, 200 consecutive patients undergoing shoulder arthroscopy were prospectively evaluated preoperatively. The hug-up test, empty can (EC test, full can (FC test, Neer impingement sign, and Hawkins-Kennedy impingement sign were used and compared statistically for their accuracy in terms of supraspinatus tears, with arthroscopic findings as the gold standard. Muscle strength was precisely quantified using an electronic digital tensiometer. Results: The prevalence of supraspinatus tears was 76.5%. The hug-up test demonstrated the highest sensitivity (94.1%, with a low negative likelihood ratio (NLR, 0.08 and comparable specificity (76.6% compared with the other four tests. The area under the receiver operating characteristic curve for the hug-up test was 0.854, with no statistical difference compared with the EC test (z = 1.438, P = 0.075 or the FC test (z = 1.498, P = 0.067. The hug-up test showed no statistical difference in terms of detecting different tear patterns according to the position (χ2 = 0.578, P = 0.898 and size (Fisher′s exact test, P > 0.999 compared with the arthroscopic examination. The interobserver reproducibility of the hug-up test was high, with a kappa coefficient of 0.823. Conclusions: The hug-up test can accurately detect supraspinatus tears with a high sensitivity, comparable specificity, and low NLR compared with the conventional

Rapid antigen detection test for respiratory syncytial virus diagnosis as a diagnostic tool

Directory of Open Access Journals (Sweden)

Flávio da Silva Mesquita

2017-05-01

Conclusions: This study demonstrated that the QuickVue® RSV Test Kit can be effective in early detection of Respiratory syncytial virus in nasopharyngeal aspirate and is reliable for use as a diagnostic tool in pediatrics.

Solitary pulmonary nodule: radiologic features and diagnostic approach

International Nuclear Information System (INIS)

Rodriguez Cambronero, Luis Enrique

2012-01-01

A literature review is conducted on the solitary pulmonary nodule, to determine the diagnostic methods and specific characteristics. The diagnostic methods used have been: chest radiography, computed tomography, positron emission tomography and magnetic resonance imaging. The radiological features are defined: location, size, definition of contours or edges (margins), densitometric and attenuation characteristics, cavitation, air bronchogram, growth, doubling time, satellite nodules, nutrient vessels [es

Definition study of a Variable Cycle Experimental Engine (VCEE) and associated test program and test plan

Science.gov (United States)

Allan, R. D.

1978-01-01

The Definition Study of a Variable Cycle Experimental Engine (VCEE) and Associated Test Program and Test Plan, was initiated to identify the most cost effective program for a follow-on to the AST Test Bed Program. The VCEE Study defined various subscale VCE's based on different available core engine components, and a full scale VCEE utilizing current technology. The cycles were selected, preliminary design accomplished and program plans and engineering costs developed for several program options. In addition to the VCEE program plans and options, a limited effort was applied to identifying programs that could logically be accomplished on the AST Test Bed Program VCE to extend the usefulness of this test hardware. Component programs were provided that could be accomplished prior to the start of a VCEE program.

Diagnostic validity of physical examination tests for common knee disorders: An overview of systematic reviews and meta-analysis.

Science.gov (United States)

Décary, Simon; Ouellet, Philippe; Vendittoli, Pascal-André; Roy, Jean-Sébastien; Desmeules, François

2017-01-01

More evidence on diagnostic validity of physical examination tests for knee disorders is needed to lower frequently used and costly imaging tests. To conduct a systematic review of systematic reviews (SR) and meta-analyses (MA) evaluating the diagnostic validity of physical examination tests for knee disorders. A structured literature search was conducted in five databases until January 2016. Methodological quality was assessed using the AMSTAR. Seventeen reviews were included with mean AMSTAR score of 5.5 ± 2.3. Based on six SR, only the Lachman test for ACL injuries is diagnostically valid when individually performed (Likelihood ratio (LR+):10.2, LR-:0.2). Based on two SR, the Ottawa Knee Rule is a valid screening tool for knee fractures (LR-:0.05). Based on one SR, the EULAR criteria had a post-test probability of 99% for the diagnosis of knee osteoarthritis. Based on two SR, a complete physical examination performed by a trained health provider was found to be diagnostically valid for ACL, PCL and meniscal injuries as well as for cartilage lesions. When individually performed, common physical tests are rarely able to rule in or rule out a specific knee disorder, except the Lachman for ACL injuries. There is low-quality evidence concerning the validity of combining history elements and physical tests. Copyright © 2016 Elsevier Ltd. All rights reserved.

Self Diagnostic Accelerometer Testing on the C-17 Aircraft

Science.gov (United States)

Tokars, Roger P.; Lekki, John D.

2013-01-01

The self diagnostic accelerometer (SDA) developed by the NASA Glenn Research Center was tested for the first time in an aircraft engine environment as part of the Vehicle Integrated Propulsion Research (VIPR) program. The VIPR program includes testing multiple critical flight sensor technologies. One such sensor, the accelerometer, measures vibrations to detect faults in the engine. In order to rely upon the accelerometer, the health of the accelerometer must be ensured. The SDA is a sensor system designed to actively determine the accelerometer structural health and attachment condition, in addition to vibration measurements. The SDA uses a signal conditioning unit that sends an electrical chirp to the accelerometer and recognizes changes in the response due to changes in the accelerometer health and attachment condition. To demonstrate the SDAs flight worthiness and robustness, multiple SDAs were mounted and tested on a C-17 aircraft engine. The engine test conditions varied from engine off, to idle, to maximum power. The SDA attachment conditions were varied from fully tight to loose. The newly developed SDA health algorithm described herein uses cross correlation pattern recognition to discriminate a healthy from a faulty SDA. The VIPR test results demonstrate for the first.

The validity of upper-limb neurodynamic tests for detecting peripheral neuropathic pain.

Science.gov (United States)

Nee, Robert J; Jull, Gwendolen A; Vicenzino, Bill; Coppieters, Michel W

2012-05-01

The validity of upper-limb neurodynamic tests (ULNTs) for detecting peripheral neuropathic pain (PNP) was assessed by reviewing the evidence on plausibility, the definition of a positive test, reliability, and concurrent validity. Evidence was identified by a structured search for peer-reviewed articles published in English before May 2011. The quality of concurrent validity studies was assessed with the Quality Assessment of Diagnostic Accuracy Studies tool, where appropriate. Biomechanical and experimental pain data support the plausibility of ULNTs. Evidence suggests that a positive ULNT should at least partially reproduce the patient's symptoms and that structural differentiation should change these symptoms. Data indicate that this definition of a positive ULNT is reliable when used clinically. Limited evidence suggests that the median nerve test, but not the radial nerve test, helps determine whether a patient has cervical radiculopathy. The median nerve test does not help diagnose carpal tunnel syndrome. These findings should be interpreted cautiously, because diagnostic accuracy might have been distorted by the investigators' definitions of a positive ULNT. Furthermore, patients with PNP who presented with increased nerve mechanosensitivity rather than conduction loss might have been incorrectly classified by electrophysiological reference standards as not having PNP. The only evidence for concurrent validity of the ulnar nerve test was a case study on cubital tunnel syndrome. We recommend that researchers develop more comprehensive reference standards for PNP to accurately assess the concurrent validity of ULNTs and continue investigating the predictive validity of ULNTs for prognosis or treatment response.

Frontline diagnostic evaluation of patients suspected of angina by coronary computed tomography reduces downstream resource utilization when compared to conventional ischemia testing

DEFF Research Database (Denmark)

Nielsen, L. H.; Markenvard, John; Jensen, Jesper Møller

2011-01-01

It has been proposed that the increasing use of coronary computed tomographic angiography (CTA) may introduce additional unnecessary diagnostic procedures. However, no previous study has assessed the impact on downstream test utilization of conventional diagnostic testing relative to CTA in patie...... prospective trials are needed in order to define the most cost-effective diagnostic use of CTA relative to conventional ischemia testing....

Clinical Evaluation of Rapid Diagnostic Test Kit for Scrub Typhus with Improved Performance.

Science.gov (United States)

Kim, Young-Jin; Park, Sungman; Premaratna, Ranjan; Selvaraj, Stephen; Park, Sang-Jin; Kim, Sora; Kim, Donghwan; Kim, Min Soo; Shin, Dong Hoon; Choi, Kyung-Chan; Kwon, Soon-Hwan; Seo, Wonjun; Lee, Nam Taek; Kim, Seung-Han; Kang, Heui Keun; Kim, Yoon-Won

2016-08-01

Diagnosis of scrub typhus is challenging due to its more than twenty serotypes and the similar clinical symptoms with other acute febrile illnesses including leptospirosis, murine typhus and hemorrhagic fever with renal syndrome. Accuracy and rapidity of a diagnostic test to Orientia tsutsugamushi is an important step to diagnose this disease. To discriminate scrub typhus from other diseases, the improved ImmuneMed Scrub Typhus Rapid Diagnostic Test (RDT) was evaluated in Korea and Sri Lanka. The sensitivity at the base of each IgM and IgG indirect immunofluorescent assay (IFA) in Korean patients was 98.6% and 97.1%, and the specificity was 98.2% and 97.7% respectively. The sensitivity and specificity for retrospective diagnosis at the base of IFA in Sri Lanka was 92.1% and 96.1%. ImmuneMed RDT was not reactive to any serum from seventeen diseases including hemorrhagic fever with renal syndrome (n = 48), leptospirosis (n = 23), and murine typhus (n = 48). ImmuneMed RDT shows superior sensitivity (98.6% and 97.1%) compared with SD Bioline RDT (84.4% at IgM and 83.3% at IgG) in Korea. The retrospective diagnosis of ImmuneMed RDT exhibits 94.0% identity with enzyme-linked Immunosorbent assay (ELISA) using South India patient serum samples. These results suggest that this RDT can replace other diagnostic tests and is applicable for global diagnosis of scrub typhus. This rapid and accurate diagnosis will be beneficial for diagnosing and managing scrub typhus.

Addressing Barriers to the Development and Adoption of Rapid Diagnostic Tests in Global Health

Directory of Open Access Journals (Sweden)

Eric Miller

2015-06-01

Full Text Available Immunochromatographic rapid diagnostic tests (RDTs have demonstrated significant potential for use as point-of- care diagnostic tests in resource-limited settings. Most notably, RDTs for malaria have reached an unparalleled level of technological maturity and market penetration, and are now considered an important complement to standard microscopic methods of malaria diagnosis. However, the technical development of RDTs for other infectious diseases, and their uptake within the global health community as a core diagnostic modality, has been hindered by a number of extant challenges. These range from technical and biological issues, such as the need for better affinity agents and biomarkers of disease, to social, infrastructural, regulatory and economic barriers, which have all served to slow their adoption and diminish their impact. In order for the immunochromatographic RDT format to be successfully adapted to other disease targets, to see widespread distribution, and to improve clinical outcomes for patients on a global scale, these challenges must be identified and addressed, and the global health community must be engaged in championing the broader use of RDTs.

Addressing Barriers to the Development and Adoption of Rapid Diagnostic Tests in Global Health

Directory of Open Access Journals (Sweden)

Eric Miller

2015-06-01

Full Text Available Immunochromatographic rapid diagnostic tests (RDTs have demonstrated significant potential for use as point-of-care diagnostic tests in resource-limited settings. Most notably, RDTs for malaria have reached an unparalleled level of technological maturity and market penetration, and are now considered an important complement to standard microscopic methods of malaria diagnosis. However, the technical development of RDTs for other infectious diseases, and their uptake within the global health community as a core diagnostic modality, has been hindered by a number of extant challenges. These range from technical and biological issues, such as the need for better affinity agents and biomarkers of disease, to social, infrastructural, regulatory and economic barriers, which have all served to slow their adoption and diminish their impact. In order for the immunochromatographic RDT format to be successfully adapted to other disease targets, to see widespread distribution, and to improve clinical outcomes for patients on a global scale, these challenges must be identified and addressed, and the global health community must be engaged in championing the broader use of RDTs.

Addressing Barriers to the Development and Adoption of Rapid Diagnostic Tests in Global Health.

Science.gov (United States)

Miller, Eric; Sikes, Hadley D

Immunochromatographic rapid diagnostic tests (RDTs) have demonstrated significant potential for use as point-of-care diagnostic tests in resource-limited settings. Most notably, RDTs for malaria have reached an unparalleled level of technological maturity and market penetration, and are now considered an important complement to standard microscopic methods of malaria diagnosis. However, the technical development of RDTs for other infectious diseases, and their uptake within the global health community as a core diagnostic modality, has been hindered by a number of extant challenges. These range from technical and biological issues, such as the need for better affinity agents and biomarkers of disease, to social, infrastructural, regulatory and economic barriers, which have all served to slow their adoption and diminish their impact. In order for the immunochromatographic RDT format to be successfully adapted to other disease targets, to see widespread distribution, and to improve clinical outcomes for patients on a global scale, these challenges must be identified and addressed, and the global health community must be engaged in championing the broader use of RDTs.

A weighted generalized score statistic for comparison of predictive values of diagnostic tests.

Science.gov (United States)

Kosinski, Andrzej S

2013-03-15

Positive and negative predictive values are important measures of a medical diagnostic test performance. We consider testing equality of two positive or two negative predictive values within a paired design in which all patients receive two diagnostic tests. The existing statistical tests for testing equality of predictive values are either Wald tests based on the multinomial distribution or the empirical Wald and generalized score tests within the generalized estimating equations (GEE) framework. As presented in the literature, these test statistics have considerably complex formulas without clear intuitive insight. We propose their re-formulations that are mathematically equivalent but algebraically simple and intuitive. As is clearly seen with a new re-formulation we presented, the generalized score statistic does not always reduce to the commonly used score statistic in the independent samples case. To alleviate this, we introduce a weighted generalized score (WGS) test statistic that incorporates empirical covariance matrix with newly proposed weights. This statistic is simple to compute, always reduces to the score statistic in the independent samples situation, and preserves type I error better than the other statistics as demonstrated by simulations. Thus, we believe that the proposed WGS statistic is the preferred statistic for testing equality of two predictive values and for corresponding sample size computations. The new formulas of the Wald statistics may be useful for easy computation of confidence intervals for difference of predictive values. The introduced concepts have potential to lead to development of the WGS test statistic in a general GEE setting. Copyright © 2012 John Wiley & Sons, Ltd.

Comparison Of Clinical, Parasitological And Serological Diagnostic ...

African Journals Online (AJOL)

Comparison Of Clinical, Parasitological And Serological Diagnostic Methods For The Definitive ... Consideringthe relative significance of these methods in the diagnosis of onchocerciasis, we ... http://dx.doi.org/10.4314/ari.v1i3.40835.

Publishing nutrition research: validity, reliability, and diagnostic test assessment in nutrition-related research.

Science.gov (United States)

Gleason, Philip M; Harris, Jeffrey; Sheean, Patricia M; Boushey, Carol J; Bruemmer, Barbara

2010-03-01

This is the sixth in a series of monographs on research design and analysis. The purpose of this article is to describe and discuss several concepts related to the measurement of nutrition-related characteristics and outcomes, including validity, reliability, and diagnostic tests. The article reviews the methodologic issues related to capturing the various aspects of a given nutrition measure's reliability, including test-retest, inter-item, and interobserver or inter-rater reliability. Similarly, it covers content validity, indicators of absolute vs relative validity, and internal vs external validity. With respect to diagnostic assessment, the article summarizes the concepts of sensitivity and specificity. The hope is that dietetics practitioners will be able to both use high-quality measures of nutrition concepts in their research and recognize these measures in research completed by others. Copyright 2010 American Dietetic Association. Published by Elsevier Inc. All rights reserved.

CT-guided transthoracic core needle biopsy for small pulmonary lesions: diagnostic performance and adequacy for molecular testing.

Science.gov (United States)

Tian, Panwen; Wang, Ye; Li, Lei; Zhou, Yongzhao; Luo, Wenxin; Li, Weimin

2017-02-01

Computed tomography (CT)-guided transthoracic needle biopsy is a well-established, minimally invasive diagnostic tool for pulmonary lesions. Few large studies have been conducted on the diagnostic performance and adequacy for molecular testing of transthoracic core needle biopsy (TCNB) for small pulmonary lesions. This study included CT-guided TCNB with 18-gauge cutting needles in 560 consecutive patients with small (≤3 cm) pulmonary lesions from January 2012 to January 2015. There were 323 males and 237 females, aged 51.8±12.7 years. The size of the pulmonary lesions was 1.8±0.6 cm. The sensitivity, specificity, accuracy and complications of the biopsies were investigated. The risk factors of diagnostic failure were assessed using univariate and multivariate analyses. The sample's adequacy for molecular testing of non-small cell lung cancer (NSCLC) was analyzed. The overall sensitivity, specificity, and accuracy for diagnosis of malignancy were 92.0% (311/338), 98.6% (219/222), and 94.6% (530/560), respectively. The incidence of bleeding complications was 22.9% (128/560), and the incidence of pneumothorax was 10.4% (58/560). Logistic multivariate regression analysis showed that the independent risk factors for diagnostic failure were a lesion size ≤1 cm [odds ratio (OR), 3.95; P=0.007], lower lobe lesions (OR, 2.83; P=0.001), and pneumothorax (OR, 1.98; P=0.004). Genetic analysis was successfully performed on 95.45% (168/176) of specimens diagnosed as NSCLC. At least 96.8% of samples with two or more passes from a lesion were sufficient for molecular testing. The diagnostic yield of small pulmonary lesions by CT-guided TCNB is high, and the procedure is relatively safe. A lesion size ≤1 cm, lower lobe lesions, and pneumothorax are independent risk factors for biopsy diagnostic failure. TCNB specimens could provide adequate tissues for molecular testing.

Recall Tests Are Effective to Detect Mild Cognitive Impairment: A Systematic Review and Meta-analysis of 108 Diagnostic Studies.

Science.gov (United States)

Tsoi, Kelvin K F; Chan, Joyce Y C; Hirai, Hoyee W; Wong, Adrian; Mok, Vincent C T; Lam, Linda C W; Kwok, Timothy C Y; Wong, Samuel Y S

2017-09-01

Mild cognitive impairment (MCI) is a prevalent symptom associated with the increased risk of dementia. There are many cognitive tests available for detection of MCI, and investigation of the diagnostic performance of the tests is deemed necessary. This study aims to evaluate the diagnostic performance of different cognitive tests used for MCI detection. A list of cognitive tests was identified in previous reviews and from online search engines. Literature searches were performed on each of the cognitive tests in MEDLINE, Embase, and PsycINFO from the earliest available dates of individual databases to December 31, 2016. Google Scholar was used as a supplementary search tool. Studies that were used to assess the diagnostic performance of the cognitive tests were extracted with inclusion and exclusion criteria. Each test's performance was compared with the standard diagnostic criteria. Bivariate random effects models were used to summarize the test performance as a point estimate for sensitivity and specificity, and presented in a summary receiver operating characteristic curve. Reporting quality and risk of bias were evaluated. A total of 108 studies with 23,546 participants were selected to evaluate 9 cognitive tests for MCI detection. Most of the studies used the Mini-Mental State Examination (MMSE) (n = 58) and the Montreal Cognitive Assessment (MoCA) (n = 35). The combined diagnostic performance of the MMSE in MCI detection was 0.71 sensitivity [95% confidence interval (CI): 0.66-0.75] and 0.74 specificity (95% CI: 0.70-0.78), and of the MoCA in MCI detection was 0.83 sensitivity (95% CI: 0.80-0.86) and 0.75 specificity (95% CI: 0.69-0.80). Among the 9 cognitive tests, recall tests showed the best diagnostic performance with 0.89 sensitivity (95% CI: 0.86-0.92) and 0.84 specificity (95% CI, 0.79-0.89). In subgroup analyses, long- or short-delay recall tests have shown better performance than immediate recall tests. Recall tests were shown to be the most

An update on feline infectious peritonitis: diagnostics and therapeutics.

Science.gov (United States)

Pedersen, Niels C

2014-08-01

This review is concerned with what has been learned about feline infectious peritonitis (FIP) diagnostics and therapeutics since the publication of an extensive overview of literature covering the period 1963-2009. Although progress has been made in both areas, obtaining a definitive diagnosis of FIP remains a problem for those veterinarians and/or cat owners who require absolute certainty. This review will cover both indirect and direct diagnostic tests for the disease and will emphasize their limitations, as well as their specificity and sensitivity. There is still no effective treatment for FIP, although there are both claims that such therapies exist and glimmers of hope coming from new therapies that are under research. FIP has also been identified in wild felids and FIP-like disease is now a growing problem among pet ferrets. Copyright © 2014 The Author. Published by Elsevier Ltd.. All rights reserved.

Reference materials for molecular diagnostics: Current achievements and future strategies.

Science.gov (United States)

Jing, Rongrong; Wang, Huimin; Ju, Shaoqing; Cui, Ming

2018-06-01

Molecular diagnoses have become more widespread in many areas of laboratory medicine where qualitative or quantitative approaches are used to detect nucleic acids. The increasing number of assay methods and the targets for molecular diagnostics contribute to variability in the test results among clinical laboratories. Thus, reference materials (RMs) are required to enhance the comparability of results. This review focuses on the definition of RMs as well as the production and characteristics of higher order RMs from different organizations and their future strategies. We describe the recent progress in RMs, including the definition of RMs by the Joint Committee for Guides in Metrology, as well as the production and characteristics of higher order RMs by international official bodies. There is an urgent need for RMs in nucleic acid testing, especially higher order RMs. To advance the harmonization and standardization of clinical nucleic acid detection, cooperation between the above organizations is proposed and different approaches to higher order RMs development are also needed. Copyright © 2018 The Canadian Society of Clinical Chemists. Published by Elsevier Inc. All rights reserved.

Evaluation of the Ortho-Clinical Diagnostics Vitros ECi Anti-HCV test: comparison with three other methods.

Science.gov (United States)

Watterson, Jeannette M; Stallcup, Paulina; Escamilla, David; Chernay, Patrick; Reyes, Alfred; Trevino, Sylvia C

2007-01-01

After observing a high incidence of low positive hepatitis C virus (HCV) antibody screens by the Ortho-Clinical Vitros ECi test (Orthoclinical Diagnostics, Raritan, NJ), we compared results against those obtained using another chemiluminescent analyzer, as well as two U.S. Food and Drug Administration (FDA)-approved confirmatory methodologies. To ascertain the true anti-HCV status of samples deemed low-positive by the Ortho-Clinical Vitros ECi test, we tested samples using the ADVIA Centaur HCV screen test (Siemens Medical Solutions Diagnostics), the Chiron recombinant immunoblot assay (RIBA) test (Chiron Corp., Emeryville, CA), and the Roche COBAS Amplicor HCV qualitative test (Roche Diagnostics, Indianapolis, IN) in a series of studies. Of 94 specimens positive by Vitros ECi, 19% were observed to be negative by Centaur. A separate study of 91 samples with signal-to-cutoff (s/co) values less than 8.0 showed that all but one was negative for HCV ribonucleic acid (RNA). In comparison with RIBA, 100% (77) samples positive by the Vitros ECi test with s/co values less than 12.0 were negative or indeterminate by RIBA. A final study comparing all four methods side-by-side showed 63% disagreement by Centaur for Vitros ECi low-positive samples, 75% disagreement by RIBA, and 97% disagreement by polymerase chain reaction (PCR). In conclusion, the Ortho-Clinical Vitros ECi Anti-HCV test yields a high rate of false-positive results in the low s/co range in our patient population. (c) 2007 Wiley-Liss, Inc.

Implementation of Rapid Molecular Infectious Disease Diagnostics: the Role of Diagnostic and Antimicrobial Stewardship.

Science.gov (United States)

Messacar, Kevin; Parker, Sarah K; Todd, James K; Dominguez, Samuel R

2017-03-01

New rapid molecular diagnostic technologies for infectious diseases enable expedited accurate microbiological diagnoses. However, diagnostic stewardship and antimicrobial stewardship are necessary to ensure that these technologies conserve, rather than consume, additional health care resources and optimally affect patient care. Diagnostic stewardship is needed to implement appropriate tests for the clinical setting and to direct testing toward appropriate patients. Antimicrobial stewardship is needed to ensure prompt appropriate clinical action to translate faster diagnostic test results in the laboratory into improved outcomes at the bedside. This minireview outlines the roles of diagnostic stewardship and antimicrobial stewardship in the implementation of rapid molecular infectious disease diagnostics. Copyright © 2017 American Society for Microbiology.

Towards the definition of Institutional diagnostic reference levels in paediatric interventional cardiology procedures in Greece.

Science.gov (United States)

Kottou, S; Kollaros, N; Plemmenos, C; Mastorakou, I; Apostolopoulou, S C; Tsapaki, V

2018-02-01

This study aimed to evaluate paediatric radiation doses in a dedicated cardiology hospital, with the objective of characterising patterns in dose variation. The ultimate purpose was to define Local (Institutional) Diagnostic Reference Levels (LDRLs) for different types of paediatric cardiac interventional procedures (IC), according to patient age. From a total of 710 cases performed during three consecutive years, by operators with more than 15 years of experience, the age was noted in only 477 IC procedures. The median values obtained for Fluoroscopy Time (FT), Number of Frames (N) and Kerma Area Product (P KA ) by age range were 5.8 min, 1322 and 2.0 Gy.cm 2 for definition of LDRLs presents challenges mainly due to the multiple clinical and technical factors affecting the outcome. On the other hand the lack of paediatric IC DRLs makes the identification of good practices more difficult. A consensus is needed on IC procedures nomenclature and grouping in order to allow a common assessment and comparison of doses. Copyright © 2018 Associazione Italiana di Fisica Medica. Published by Elsevier Ltd. All rights reserved.

Evaluation of the Revised Algorithm of Autism Diagnostic Observation Schedule (ADOS) in the Diagnostic Investigation of High-Functioning Children and Adolescents with Autism Spectrum Disorders

Science.gov (United States)

Kamp-Becker, Inge; Ghahreman, Mardjan; Heinzel-Gutenbrunner, Monika; Peters, Mira; Remschmidt, Helmut; Becker, Katja

2013-01-01

The Autism Diagnostic Observation Schedule (ADOS) is a semi-structured, standardized assessment designed for use in diagnostic evaluation of individuals with suspected autism spectrum disorder (ASD). The ADOS has been effective in categorizing children who definitely have autism or not, but has lower specificity and sometimes sensitivity for…

DIM and diagnostic placement for NIF experiments

International Nuclear Information System (INIS)

Kalantar, D.

1999-01-01

The input that has been provided on the NIF experiment setup sheets has allowed us to review the diagnostic and DIM placement as well as the baseline unconverted light management plan. We have done an iteration to identify common diagnostic lines of sight, and with additional requirements defined by specific experiments, we propose (1) a baseline plan for DIM placement requiring only five DIMs that may be moved between up to seven DIM ports, and (2) a modified baseline unconverted light management plan. We request additional input to identify primary vs. secondary diagnostics for each experiment definition

Real-world utilization of molecular diagnostic testing and matched drug therapies in the treatment of metastatic cancers.

Science.gov (United States)

Chawla, Anita; Peeples, Miranda; Li, Nanxin; Anhorn, Rachel; Ryan, Jason; Signorovitch, James

2018-06-01

To assess the frequency of biopsies and molecular diagnostic testing (human DNA/RNA analysis), anti-cancer drug use (genomically-matched targeted therapy [GMTT], unmatched targeted therapy [UTT], endocrine therapy [ET], and chemotherapy [CT]), and medical service costs among adults with metastatic cancer. Adults diagnosed with metastatic breast, non-small cell lung (NSCLC), colorectal, head and neck, ovarian, and uterine cancer (2010Q1-2015Q1) were identified in the OptumHealth Care Solutions claims database and followed from first metastatic diagnosis for ≥1 month and until the end of data availability. Utilization was assessed for each cancer cohort (all and patients aged ≥65 years); per-patient-per-month (PPPM) medical service costs were assessed for all patients. Testing frequency estimates were applied to Surveillance, Epidemiology, and End Results Program data to estimate the number of untested patients (2010-2014). Patients with metastatic cancer (n = 8,193; breast [n = 3,414], NSCLC [n = 2,231], colorectal [n = 1,611], head and neck [n = 511], ovarian [n = 275], and uterine [n = 151]) were 63 years old (mean), with 11.1-22.2 months of observation. Biopsy and molecular diagnostic testing frequencies ranged from 7% (uterine) to 73% (ovarian), and from 34% (head and neck) to 52% (breast), respectively. Few were treated with GMTT (breast, 11%; NSCLC, 9%; colorectal, 6%). Treatment with UTT ranged from 0.7% (uterine) to 21% (colorectal). Biopsy, diagnostic testing, and anti-cancer drug therapy were less frequent for those ≥65 years. Medical service costs (PPPM, mean) ranged from $6,618 (head and neck) to $9,940 (ovarian). The estimated number of untested new patients with metastatic cancer was 636,369 (all) and 341,397 (≥65). In addition to the limitations of claims analyses, diagnostic testing frequency may be under-estimated if patients underwent testing prior to study inclusion. The low frequency of molecular diagnostic

Post-mortem diagnostics in cases of sepsis. Part 1. Aetiology, epidemiology and microbiological tests

Directory of Open Access Journals (Sweden)

Marta Rorat

2015-03-01

Full Text Available Clinical practice has an effective methodology of diagnostic procedures to be followed in cases of sepsis. However, there are as yet no corresponding standards of action in post-mortem diagnostics. The scope of examinations is limited to an autopsy and histopathological tests. This situation may lead to errors in medico-legal opinions on the cause of death and in the assessment of appropriateness of medical procedures. In cases of suspected sepsis, medico-legal investigations require obtaining detailed information about the circumstances of death (including symptoms and results of intravital examinations before autopsy is performed, as well as sterile collection of specimens for microbiological tests and interpretation of their results on the basis of knowledge of epidemiology, pathophysiology and clinical progression of sepsis.

A Global Comparative Evaluation of Commercial Immunochromatographic Rapid Diagnostic Tests for Visceral Leishmaniasis

NARCIS (Netherlands)

Cunningham, Jane; Hasker, Epco; Das, Pradeep; El Safi, Sayda; Goto, Hiro; Mondal, Dinesh; Mbuchi, Margaret; Mukhtar, Maowia; Rabello, Ana; Rijal, Suman; Sundar, Shyam; Wasunna, Monique; Adams, Emily; Menten, Joris; Peeling, Rosanna; Boelaert, Marleen; Khanal, Basudha; Das, Murari; Oliveira, Edward; de Assis, Tália Machado; Costa, Dorcas Lamounier; Bhaskar, Khondaker Rifathassan; Huda, M. Mamun; Hassan, Mukidul; Abdoun, Asim Osman; Awad, Aymen; Osman, Mohamed; Prajapati, Dinesh Kumar; Gidwani, Kamlesh; Tiwary, Puja; Paniago, Anamaria Mello Miranda; Sanchez, Maria Carmen Arroyo; Celeste, Beatriz Julieta; Jacquet, Diane; Magiri, Charles; Muia, A.; Kesusu, J.; Ageed, Al Farazdag; Galal, Nuha; Osman, Osman Salih; Gupta, A. K.; Bimal, Afrad S.; Das, V. N. R.

2012-01-01

Background. Poor access to diagnosis stymies control of visceral leishmaniasis (VL). Antibody-detecting rapid diagnostic tests (RDTs) can be performed in peripheral health settings. However, there are many brands available and published reports of variable accuracy. Methods. Commercial VL RDTs

The impact of a computerised test of attention and activity (QbTest) on diagnostic decision-making in children and young people with suspected attention deficit hyperactivity disorder: single-blind randomised controlled trial.

Science.gov (United States)

Hollis, Chris; Hall, Charlotte L; Guo, Boliang; James, Marilyn; Boadu, Janet; Groom, Madeleine J; Brown, Nikki; Kaylor-Hughes, Catherine; Moldavsky, Maria; Valentine, Althea Z; Walker, Gemma M; Daley, David; Sayal, Kapil; Morriss, Richard

2018-04-26

Diagnosis of attention deficit hyperactivity disorder (ADHD) relies on subjective methods which can lead to diagnostic uncertainty and delay. This trial evaluated the impact of providing a computerised test of attention and activity (QbTest) report on the speed and accuracy of diagnostic decision-making in children with suspected ADHD. Randomised, parallel, single-blind controlled trial in mental health and community paediatric clinics in England. Participants were 6-17 years-old and referred for ADHD diagnostic assessment; all underwent assessment-as-usual, plus QbTest. Participants and their clinician were randomised to either receive the QbTest report immediately (QbOpen group) or the report was withheld (QbBlind group). The primary outcome was number of consultations until a diagnostic decision confirming/excluding ADHD within 6-months from baseline. Health economic cost-effectiveness and cost utility analysis was conducted. Assessing QbTest Utility in ADHD: A Randomised Controlled Trial was registered at ClinicalTrials.gov (https://clinicaltrials.gov/ct2/show/NCT02209116). One hundred and thirty-two participants were randomised to QbOpen group (123 analysed) and 135 to QbBlind group (127 analysed). Clinicians with access to the QbTest report (QbOpen) were more likely to reach a diagnostic decision about ADHD (hazard ratio 1.44, 95% CI 1.04-2.01). At 6-months, 76% of those with a QbTest report had received a diagnostic decision, compared with 50% without. QbTest reduced appointment length by 15% (time ratio 0.85, 95% CI 0.77-0.93), increased clinicians' confidence in their diagnostic decisions (odds ratio 1.77, 95% CI 1.09-2.89) and doubled the likelihood of excluding ADHD. There was no difference in diagnostic accuracy. Health economic analysis showed a position of strict dominance; however, cost savings were small suggesting that the impact of providing the QbTest report within this trial can best be viewed as 'cost neutral'. QbTest may increase the

Synthesis of evidence of diagnostic tests and preventive programs identifying pre-diabetes type

Directory of Open Access Journals (Sweden)

Dagmar Tučková

2015-09-01

Full Text Available Introduction: Type 2 diabetes mellitus (T2D has become the main type of diabetes in children and it is expected that in countries with high income diabetes it is projected to be one of the leading causes of death by 2030. Another fact is that programs and tests diagnosing pre-diabetes type 2 (T2P-DMC are missing. Methods: The aim of the paper is to present the steps for the synthesis of the evidence within the brand new type of the systematic review (SR: SR of diagnostic test accuracy (DTA. Using the acronym PIRD it was developed a review question, search strategy and inclusion and exclusion criteria. Results: The initial search was done in two databases (MedLine and Cinahl with 2 025 results. The second search after the improvement of the sensitivity and the specificity was done in 15 databases with 3 681 results. Conclusion: This methodological paper introduces how to conduct the systematic review protocols of diagnostic test accuracy on the example of T2P-DMC.

Quality control test solutions for diagnostic radiology, nuclear medicine and health physics with PTW equipment

International Nuclear Information System (INIS)

Froescher, Olga

2007-01-01

Complete test of publication follows. In 1922 PTW-Freiburg was founded to produce and market a revolutionary new electromechanical component for measuring very small electrical charges. Today PTW is the specialist and one of the global market leaders for manufacturing and supplying high-quality products in diagnostic radiology, nuclear medicine, radiation therapy and health physics. The quality control of X-ray images is influenced by a number of parameters. To maintain a consistent performance of X-ray installations, quality checks have to be conducted regularly. PTW offers a variety of diagnostic test tools for different X-ray devices, and therefore to reduce patient exposure and costs for X-ray departments. PTW's 'Code of Practice' defines in an easy and compact way how to perform quality control measurements on different diagnostic X-ray installations. The necessary equipment for measuring main parameters as well as acceptable limits are mentioned accordingly. The 'Code of Practice' bases on actual standards.

Diagnostic grand rounds: A new teaching concept to train diagnostic reasoning

International Nuclear Information System (INIS)

Stieger, Stefan; Praschinger, Andrea; Kletter, Kurt; Kainberger, Franz

2011-01-01

Introduction: Diagnostic reasoning is a core skill in teaching and learning in undergraduate curricula. Diagnostic grand rounds (DGRs) as a subform of grand rounds are intended to train the students' skills in the selection of appropriate tests and in the interpretation of test results. The aim of this study was to test DGRs for their ability to improve diagnostic reasoning by using a pre-post-test design. Methods: During one winter term, all 398 fifth-year students (36.1% male, 63.9% female) solved 23 clinical cases presented in 8 DGRs. In an online questionnaire, a Diagnostic Thinking Inventory (DTI) with 41 items was evaluated for flexibility in thinking and structure of knowledge in memory. Results were correlated with those from a summative multiple-choice knowledge test and of the learning objectives in a logbook. Results: The students' DTI scores in the post-test were significantly higher than those reported in the pre-test. DTI scores at either testing time did not correlate with medical knowledge as assessed by a multiple-choice knowledge test. Abilities acquired during clinical clerkships as documented in a logbook could only account for a small proportion of the increase in the flexibility subscale score. This effect still remained significant after accounting for potential confounders. Conclusion: Establishing DGRs proofed to be an effective way of successfully improving both students' diagnostic reasoning and the ability to select the appropriate test method in routine clinical practice.

Diagnostic grand rounds: A new teaching concept to train diagnostic reasoning

Energy Technology Data Exchange (ETDEWEB)

Stieger, Stefan, E-mail: stefan.stieger@univie.ac.at [Department of Basic Psychological Research, School of Psychology, University of Vienna, Liebiggasse 5, A-1010 Vienna (Austria); Praschinger, Andrea, E-mail: andrea.praschinger@meduniwien.ac.at [Core Unit for Medical Education (BEMAW), Medical University of Vienna, Spitalgasse 23, BT87, P.O. 10, A-1097 Vienna (Austria); Kletter, Kurt, E-mail: kurt.kletter@meduniwien.ac.at [Department of Nuclear Medicine, General Hospital of Vienna, Waehringer Guertel 18-20, A-1090 Vienna (Austria); Kainberger, Franz, E-mail: franz.kainberger@meduniwien.ac.at [Department of Radiology, General Hospital of Vienna, Waehringer Guertel 18-20, A-1090 Vienna (Austria)

2011-06-15

Introduction: Diagnostic reasoning is a core skill in teaching and learning in undergraduate curricula. Diagnostic grand rounds (DGRs) as a subform of grand rounds are intended to train the students' skills in the selection of appropriate tests and in the interpretation of test results. The aim of this study was to test DGRs for their ability to improve diagnostic reasoning by using a pre-post-test design. Methods: During one winter term, all 398 fifth-year students (36.1% male, 63.9% female) solved 23 clinical cases presented in 8 DGRs. In an online questionnaire, a Diagnostic Thinking Inventory (DTI) with 41 items was evaluated for flexibility in thinking and structure of knowledge in memory. Results were correlated with those from a summative multiple-choice knowledge test and of the learning objectives in a logbook. Results: The students' DTI scores in the post-test were significantly higher than those reported in the pre-test. DTI scores at either testing time did not correlate with medical knowledge as assessed by a multiple-choice knowledge test. Abilities acquired during clinical clerkships as documented in a logbook could only account for a small proportion of the increase in the flexibility subscale score. This effect still remained significant after accounting for potential confounders. Conclusion: Establishing DGRs proofed to be an effective way of successfully improving both students' diagnostic reasoning and the ability to select the appropriate test method in routine clinical practice.

Diagnostic value of patient characteristics, history, and six clinical tests for traumatic anterior shoulder instability

NARCIS (Netherlands)

van Kampen, D.A.; van den Berg, T.; van der Woude, H.J.; Castelein, R.M.; Terwee, C.B.; Willems, W.J.

2013-01-01

Background: It is unknown which combination of patient information and clinical tests might beoptimal for the diagnosis of traumatic anterior shoulder instability. This study aimed to determinethe diagnostic value of individual clinical tests and to develop a prediction model that combined patient

The bone diagnostic instrument III: Testing mouse femora

Science.gov (United States)

Randall, Connor; Mathews, Phillip; Yurtsev, Eugene; Sahar, Nadder; Kohn, David; Hansma, Paul

2009-06-01

Here we describe modifications that allow the bone diagnostic instrument (BDI) [P. Hansma et al., Rev. Sci. Instrum. 79, 064303 (2008); Rev. Sci. Instrum. 77, 075105 (2006)], developed to test human bone, to test the femora of mice. These modifications include reducing the effective weight of the instrument on the bone, designing and fabricating new probe assemblies to minimize damage to the small bone, developing new testing protocols that involve smaller testing forces, and fabricating a jig for securing the smaller bones for testing. With these modifications, the BDI was used to test the hypothesis that short-term running has greater benefit on the mechanical properties of the femur for young growing mice compared to older, skeletally mature mice. We measured elastic modulus, hardness, and indentation distance increase (IDI), which had previously been shown to be the best discriminators in model systems known to exhibit differences in mechanical properties at the whole bone level. In the young exercised murine femora, the IDI was significantly lower than in young control femora. Since IDI has a relation to postyield properties, these results suggest that exercise during bone development increases post yield mechanical competence. We were also able to measure effects of aging on bone properties with the BDI. There was a significant increase in the IDI, and a significant decrease in the elastic modulus and hardness between the young and old groups. Thus, with the modifications described here, the BDI can take measurements on mouse bones and obtain statistically significant results.

Sensitive KIT D816V mutation analysis of blood as a diagnostic test in mastocytosis

DEFF Research Database (Denmark)

Kielsgaard Kristensen, Thomas; Vestergaard, Hanne; Bindslev-Jensen, Carsten

2014-01-01

The recent progress in sensitive KIT D816V mutation analysis suggests that mutation analysis of peripheral blood (PB) represents a promising diagnostic test in mastocytosis. However, there is a need for systematic assessment of the analytical sensitivity and specificity of the approach in order...... to establish its value in clinical use. We therefore evaluated sensitive KIT D816V mutation analysis of PB as a diagnostic test in an entire case-series of adults with mastocytosis. We demonstrate for the first time that by using a sufficiently sensitive KIT D816V mutation analysis, it is possible to detect...... the mutation in PB in nearly all adult mastocytosis patients. The mutation was detected in PB in 78 of 83 systemic mastocytosis (94%) and 3 of 4 cutaneous mastocytosis patients (75%). The test was 100% specific as determined by analysis of clinically relevant control patients who all tested negative. Mutation...

State of malaria diagnostic testing at clinical laboratories in the United States, 2010: a nationwide survey

Directory of Open Access Journals (Sweden)

Abanyie Francisca A

2011-11-01

Full Text Available Abstract Background The diagnosis of malaria can be difficult in non-endemic areas, such as the United States, and delays in diagnosis and errors in treatment occur too often. Methods A nationwide survey of laboratories in the United States and its nine dependent territories was conducted in 2010 to determine factors that may contribute to shortcomings in the diagnosis of malaria. This survey explored the availability of malaria diagnostic tests, techniques used, and reporting practices. Results The survey was completed by 201 participants. Ninety percent reported that their laboratories had at least one type of malaria diagnostic test available on-site. Nearly all of the respondents' laboratories performed thick and thin smears on-site; approximately 50% had access to molecular testing; and only 17% had access to rapid diagnostic tests on-site. Seventy-three percent reported fewer than five confirmed cases of malaria in their laboratory during the 12-month period preceding the survey. Twenty-eight percent stated that results of species identification took more than 24 hours to report. Only five of 149 respondents that performed testing 24 hours a day, 7 days a week complied with all of the Clinical and Laboratory Standards Institute (CLSI guidelines for analysis and reporting of results. Conclusion Although malaria diagnostic testing services were available to a majority of U.S. laboratories surveyed, very few were in complete compliance with all of the CLSI guidelines for analysis and reporting of results, and most respondents reported very few cases of malaria annually. Laboratories' difficulty in adhering to the rigorous CLSI guidelines and their personnel's lack of practice and proficiency may account for delays and errors in diagnosis. It is recommended that laboratories that infrequently process samples for malaria seek opportunities for practice and proficiency training annually and take advantage of available resources to assist in

Is Serial Testing Required to Diagnose Imported Malaria in the Era of Rapid Diagnostic Tests?

Science.gov (United States)

Pasricha, Janet M.; Juneja, Surender; Manitta, Joseph; Whitehead, Susan; Maxwell, Ellen; Goh, Wai-Keong; Pasricha, Sant-Rayn; Eisen, Damon P.

2013-01-01

Exclusion of malaria traditionally requires three negative serial thick and thin blood films. However, many clinical laboratories now routinely perform rapid diagnostic tests (RDTs) in addition to blood films when malaria is suspected. We sought to determine whether serial testing is necessary in this setting. We examined 388 cases of malaria diagnosed during 1999–2010 at three laboratories in Melbourne, Australia. For each case, we ascertained whether the diagnosis was made on initial or follow-up testing. Nine cases (3.5%) were diagnosed after a negative initial blood film and RDT: 7 Plasmodium vivax, 1 P. ovale, and 1 P. falciparum. Of four case-patients with P. vivax in which clinical data were available, all had recent exposure to antimalarial medication. Our data suggest that among patients who have not received recent anti-malarial therapy, and when RDTs are performed and blood films are prepared, most malaria diagnoses are made by using the first set of tests. PMID:23208885

Diagnosis of feline infectious peritonitis: Update on evidence supporting available tests.

Science.gov (United States)

Tasker, Séverine

2018-03-01

Practical relevance: Feline coronavirus (FCoV) infection is very common in cats, usually causing only mild intestinal signs such as diarrhoea. Up to 10% of FCoV infections, however, result in the fatal disease feline infectious peritonitis (FIP). Clinical challenges: Obtaining a definitive diagnosis of FIP based on non-invasive approaches is difficult. Confirmation of the disease relies on finding appropriate cytological or histopathological changes in association with positive immunostaining for FCoV antigen. In FIP cases with effusions, cytology and immunostaining on effusion samples can be relatively easy to perform; otherwise obtaining diagnostic samples is more challenging and collection of biopsies from tissues with gross lesions is necessary. In the absence of a definitive diagnosis, a high index of suspicion of FIP may be obtained from the cat's signalment and history, combined with findings on clinical examination and laboratory test results. If largely consistent with FIP, these can be used as a basis for discussion with the owner about whether additional, more invasive, diagnostic tests are warranted. In some cases it may be that euthanasia is discussed as an alternative to pursuing a definitive diagnosis ante-mortem, especially if financial limitations exist or where there are concerns over a cat's ability to tolerate invasive diagnostic procedures. Ideally, the diagnosis should be confirmed in such patients from samples taken at post-mortem examination. Global importance: FIP occurs wherever FCoV infection is present in cats, which equates to most parts of the world. Evidence base: This review provides a comprehensive overview of how to approach the diagnosis of FIP, focusing on the tests available to the veterinary practitioner and recently published evidence supporting their use.

Reliability of case definitions for public health surveillance assessed by Round-Robin test methodology

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Claus Hermann

2006-05-01

Full Text Available Abstract Background Case definitions have been recognized to be important elements of public health surveillance systems. They are to assure comparability and consistency of surveillance data and have crucial impact on the sensitivity and the positive predictive value of a surveillance system. The reliability of case definitions has rarely been investigated systematically. Methods We conducted a Round-Robin test by asking all 425 local health departments (LHD and the 16 state health departments (SHD in Germany to classify a selection of 68 case examples using case definitions. By multivariate analysis we investigated factors linked to classification agreement with a gold standard, which was defined by an expert panel. Results A total of 7870 classifications were done by 396 LHD (93% and all SHD. Reporting sensitivity was 90.0%, positive predictive value 76.6%. Polio case examples had the lowest reporting precision, salmonellosis case examples the highest (OR = 0.008; CI: 0.005–0.013. Case definitions with a check-list format of clinical criteria resulted in higher reporting precision than case definitions with a narrative description (OR = 3.08; CI: 2.47–3.83. Reporting precision was higher among SHD compared to LHD (OR = 1.52; CI: 1.14–2.02. Conclusion Our findings led to a systematic revision of the German case definitions and build the basis for general recommendations for the creation of case definitions. These include, among others, that testable yes/no criteria in a check-list format is likely to improve reliability, and that software used for data transmission should be designed in strict accordance with the case definitions. The findings of this study are largely applicable to case definitions in many other countries or international networks as they share the same structural and editorial characteristics of the case definitions evaluated in this study before their revision.

A Three-Tier Diagnostic Test to Assess Pre-Service Teachers' Misconceptions about Global Warming, Greenhouse Effect, Ozone Layer Depletion, and Acid Rain

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Arslan, Harika Ozge; Cigdemoglu, Ceyhan; Moseley, Christine

2012-01-01

This study describes the development and validation of a three-tier multiple-choice diagnostic test, the atmosphere-related environmental problems diagnostic test (AREPDiT), to reveal common misconceptions of global warming (GW), greenhouse effect (GE), ozone layer depletion (OLD), and acid rain (AR). The development of a two-tier diagnostic test…

Diagnostic accuracy of tests to detect Hepatitis C antibody: a meta-analysis and review of the literature.

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Tang, Weiming; Chen, Wen; Amini, Ali; Boeras, Debi; Falconer, Jane; Kelly, Helen; Peeling, Rosanna; Varsaneux, Olivia; Tucker, Joseph D; Easterbrook, Philippa

2017-11-01

Although direct-acting antivirals can achieve sustained virological response rates greater than 90% in Hepatitis C Virus (HCV) infected persons, at present the majority of HCV-infected individuals remain undiagnosed and therefore untreated. While there are a wide range of HCV serological tests available, there is a lack of formal assessment of their diagnostic performance. We undertook a systematic review and meta-analysis to evaluate he diagnostic accuracy of available rapid diagnostic tests (RDT) and laboratory based EIA assays in detecting antibodies to HCV. We used the PRISMA checklist and Cochrane guidance to develop our search protocol. The search strategy was registered in PROSPERO (CRD42015023567). The search focused on hepatitis C, diagnostic tests, and diagnostic accuracy within eight databases (MEDLINE, EMBASE, the Cochrane Central Register of Controlled Trials, Science Citation Index Expanded, Conference Proceedings Citation Index-Science, SCOPUS, Literatura Latino-Americana e do Caribe em Ciências da Saúde and WHO Global Index Medicus. Studies were included if they evaluated an assay to determine the sensitivity and specificity of HCV antibody (HCV Ab) in humans. Two reviewers independently extracted data and performed a quality assessment of the studies using the QUADAS tool. We pooled test estimates using the DerSimonian-Laird method, by using the software R and RevMan. 5.3. A total of 52 studies were identified that included 52,673 unique test measurements. Based on five studies, the pooled sensitivity and specificity of HCV Ab rapid diagnostic tests (RDTs) were 98% (95% CI 98-100%) and 100% (95% CI 100-100%) compared to an enzyme immunoassay (EIA) reference standard. High HCV Ab RDTs sensitivity and specificity were observed across screening populations (general population, high risk populations, and hospital patients) using different reference standards (EIA, nucleic acid testing, immunoblot). There were insufficient studies to undertake

Diagnostic value of R wave amplitude changes during exercise testing after myocardial infarction

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de Hert, S.; Vrints, C.; Vanagt, E.; Snoeck, J.

1986-01-01

To determine the diagnostic value of R wave amplitude changes occurring during exercise testing after myocardial infarction, exercise ECG's and coronary angiograms were reviewed in 76 postinfarction patients and in 40 patients with normal coronary arteries. During exercise, an increase in R wave

Diagnostic testing for celiac disease among patients with abdominal symptoms a systematic review

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van der Windt, D.A.W.M.; Jellema, A.P.; Mulder, C.J.J.; Kneepkens, C.M.F.; van der Horst, H.E.

2010-01-01

Context: The symptoms and consequences of celiac disease usually resolve with a lifelong gluten-free diet. However, clinical presentation is variable and most patients presenting with abdominal symptoms in primary care will not have celiac disease and unnecessary diagnostic testing should be

Diagnostic testing for celiac disease among patients with abdominal symptoms: a systematic review

NARCIS (Netherlands)

van der Windt, Daniëlle A. W. M.; Jellema, Petra; Mulder, Chris J.; Kneepkens, C. M. Frank; van der Horst, Henriëtte E.

2010-01-01

The symptoms and consequences of celiac disease usually resolve with a lifelong gluten-free diet. However, clinical presentation is variable and most patients presenting with abdominal symptoms in primary care will not have celiac disease and unnecessary diagnostic testing should be avoided. To

Diagnostic performance of serological tests to detect antibodies against acute scrub typhus infection in central India

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Kiran Pote

2018-01-01

Full Text Available Background: Differentiating scrub typhus from other acute febrile illness is difficult due to non specificity of clinical symptoms and relative absence of eschar in Indian population. The diagnosis thus relies mainly on laboratory tests. Antibody based serological tests are mainstay of scrub typhus diagnosis. Here, we evaluated the diagnostic performance of IgM ELISA, IgM IFA and ICT to detect antibodies against O. tsutsugamushi in acute serum of febrile patients. Methodology: The serum samples from 600 randomly selected patients suffering from acute undifferentiated fever were tested by all the three tests mentioned above. We used latent class analysis to generate unbiased results as all the tests for scrub typhus diagnosis are imperfect and none of them can be considered as reference standard. Results: We found that IgM ELISA with cutoff titer 0.5 OD has high diagnostic accuracy (sensitivity 99.9% and specificity 99.15 than IgM IFA (sensitivity 96.8% and specificity 99.7% for scrub typhus diagnosis. ICT used in our study had very high specificity 100% but low sensitivity (38% which would limit its use for acute serum samples. ICT being a screening or point of care test, has to be more sensitive while some compromise with specificity is affordable. Hence, optimal cutoff for ICT should be evaluated under different settings. Conclusion: IgM ELISA being simple and affordable could be an alternative diagnostic test to IgM IFA which is subjective and costly.

Diagnostic performance of serological tests to detect antibodies against acute scrub typhus infection in central India.

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Pote, Kiran; Narang, Rahul; Deshmukh, Pradeep

2018-01-01

Differentiating scrub typhus from other acute febrile illness is difficult due to non specificity of clinical symptoms and relative absence of eschar in Indian population. The diagnosis thus relies mainly on laboratory tests. Antibody based serological tests are mainstay of scrub typhus diagnosis. Here, we evaluated the diagnostic performance of IgM ELISA, IgM IFA and ICT to detect antibodies against O. tsutsugamushi in acute serum of febrile patients. The serum samples from 600 randomly selected patients suffering from acute undifferentiated fever were tested by all the three tests mentioned above. We used latent class analysis to generate unbiased results as all the tests for scrub typhus diagnosis are imperfect and none of them can be considered as reference standard. We found that IgM ELISA with cutoff titer 0.5 OD has high diagnostic accuracy (sensitivity 99.9% and specificity 99.15) than IgM IFA (sensitivity 96.8% and specificity 99.7%) for scrub typhus diagnosis. ICT used in our study had very high specificity 100% but low sensitivity (38%) which would limit its use for acute serum samples. ICT being a screening or point of care test, has to be more sensitive while some compromise with specificity is affordable. Hence, optimal cutoff for ICT should be evaluated under different settings. IgM ELISA being simple and affordable could be an alternative diagnostic test to IgM IFA which is subjective and costly.

Physical examination tests of the shoulder: a systematic review and meta-analysis of diagnostic test performance.

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Gismervik, Sigmund Ø; Drogset, Jon O; Granviken, Fredrik; Rø, Magne; Leivseth, Gunnar

2017-01-25

Physical examination tests of the shoulder (PETS) are clinical examination maneuvers designed to aid the assessment of shoulder complaints. Despite more than 180 PETS described in the literature, evidence of their validity and usefulness in diagnosing the shoulder is questioned. This meta-analysis aims to use diagnostic odds ratio (DOR) to evaluate how much PETS shift overall probability and to rank the test performance of single PETS in order to aid the clinician's choice of which tests to use. This study adheres to the principles outlined in the Cochrane guidelines and the PRISMA statement. A fixed effect model was used to assess the overall diagnostic validity of PETS by pooling DOR for different PETS with similar biomechanical rationale when possible. Single PETS were assessed and ranked by DOR. Clinical performance was assessed by sensitivity, specificity, accuracy and likelihood ratio. Six thousand nine-hundred abstracts and 202 full-text articles were assessed for eligibility; 20 articles were eligible and data from 11 articles could be included in the meta-analysis. All PETS for SLAP (superior labral anterior posterior) lesions pooled gave a DOR of 1.38 [1.13, 1.69]. The Supraspinatus test for any full thickness rotator cuff tear obtained the highest DOR of 9.24 (sensitivity was 0.74, specificity 0.77). Compression-Rotation test obtained the highest DOR (6.36) among single PETS for SLAP lesions (sensitivity 0.43, specificity 0.89) and Hawkins test obtained the highest DOR (2.86) for impingement syndrome (sensitivity 0.58, specificity 0.67). No single PETS showed superior clinical test performance. The clinical performance of single PETS is limited. However, when the different PETS for SLAP lesions were pooled, we found a statistical significant change in post-test probability indicating an overall statistical validity. We suggest that clinicians choose their PETS among those with the highest pooled DOR and to assess validity to their own specific clinical

Skeletal diseases. Diagnostic clinical radiology and differential diagnostics. 2. rev. and enl. ed.

International Nuclear Information System (INIS)

Freyschmidt, J.

1997-01-01

The book focuses on the diagnostic evaluation of idiopathic diseases of the skeleton and bone joints, also including the fundamental healing processes of bone fractures, particularly of stress-induced and pathologic fractures. Ample space has been given to the description and imaging of the course of diseases under treatment by up-to-date therapies, as e.g. for ostitis deformans Paget's disease, or skeletal metastases. This second edition of the book incorporates the progress achieved over the last five years in skeletal diagnostics. The advances in this field have been resulting from basic research work, for instance in molecular biology, or from a variety of completed studies relating to clinical medicine, laboratory chemistry, histopathology and radiology of skeletal diseases, and from experience obtained with the diagnostic radiology methods and techniques, with the potentials and constraints of magnetic resonance imaging (MRI) today being more critically assessed than five years ago. MRI is a modality currently meeting with interest in the context of search for additional diagnostic information, new definition of complete pictures of diseases, or false or overinterpretation of diagnostic findings. (orig./MG). 431 figs [de

Clinical relevance of the proposed sexual addiction diagnostic criteria: relation to the Sexual Addiction Screening Test-Revised.

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Carnes, Patrick J; Hopkins, Tiffany A; Green, Bradley A

2014-01-01

The present article examines and compares the various diagnostic rubrics proposed to codify symptoms of sexual addiction, and then briefly summarizes the ongoing controversy on whether sexual addiction is a valid construct. Using the diagnostic criteria proposed by , the prevalence rate of each criterion is examined in terms of scores on the Sexual Addiction Screening Test-Revised scales (). Differences in diagnostic criteria endorsement associated with sex, sexual orientation, and setting were also explored. Results from a clinical sample of men and women seeking treatment for sexual addiction demonstrated clinical relevance of the criteria, in that all but 3 criteria are endorsed at more than 50% of participants screening positive for sexual addiction on the Sexual Addiction Screening Test-Revised. Sex differences were also noted for endorsement rates of several of the criteria. Finally, several proposed criteria may pose a higher clinical threshold and thus be utilized by clinicians to identify patients with increased pathology. Results are discussed in the context of existing diagnostic frameworks across etiological perspectives.

Evidence synthesis to inform model-based cost-effectiveness evaluations of diagnostic tests: a methodological review of health technology assessments

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Bethany Shinkins

2017-04-01

Full Text Available Abstract Background Evaluations of diagnostic tests are challenging because of the indirect nature of their impact on patient outcomes. Model-based health economic evaluations of tests allow different types of evidence from various sources to be incorporated and enable cost-effectiveness estimates to be made beyond the duration of available study data. To parameterize a health-economic model fully, all the ways a test impacts on patient health must be quantified, including but not limited to diagnostic test accuracy. Methods We assessed all UK NIHR HTA reports published May 2009-July 2015. Reports were included if they evaluated a diagnostic test, included a model-based health economic evaluation and included a systematic review and meta-analysis of test accuracy. From each eligible report we extracted information on the following topics: 1 what evidence aside from test accuracy was searched for and synthesised, 2 which methods were used to synthesise test accuracy evidence and how did the results inform the economic model, 3 how/whether threshold effects were explored, 4 how the potential dependency between multiple tests in a pathway was accounted for, and 5 for evaluations of tests targeted at the primary care setting, how evidence from differing healthcare settings was incorporated. Results The bivariate or HSROC model was implemented in 20/22 reports that met all inclusion criteria. Test accuracy data for health economic modelling was obtained from meta-analyses completely in four reports, partially in fourteen reports and not at all in four reports. Only 2/7 reports that used a quantitative test gave clear threshold recommendations. All 22 reports explored the effect of uncertainty in accuracy parameters but most of those that used multiple tests did not allow for dependence between test results. 7/22 tests were potentially suitable for primary care but the majority found limited evidence on test accuracy in primary care settings

Enhancing case definitions for surveillance of human monkeypox in the Democratic Republic of Congo.

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Lynda Osadebe

2017-09-01

Full Text Available Human monkeypox (MPX occurs at appreciable rates in the Democratic Republic of Congo (DRC. Infection with varicella zoster virus (VZV has a similar presentation to that of MPX, and in areas where MPX is endemic these two illnesses are commonly mistaken. This study evaluated the diagnostic utility of two surveillance case definitions for MPX and specific clinical characteristics associated with laboratory-confirmed MPX cases.Data from a cohort of suspect MPX cases (identified by surveillance over the course of a 42 month period during 2009-2014 from DRC were used; real-time PCR diagnostic test results were used to establish MPX and VZV diagnoses. A total of 333 laboratory-confirmed MPX cases, 383 laboratory-confirmed VZV cases, and 36 cases that were determined to not be either MPX or VZV were included in the analyses. Significant (p<0.05 differences between laboratory-confirmed MPX and VZV cases were noted for several signs/symptoms including key rash characteristics. Both surveillance case definitions had high sensitivity and low specificities for individuals that had suspected MPX virus infections. Using 12 signs/symptoms with high sensitivity and/or specificity values, a receiver operator characteristic analysis showed that models for MPX cases that had the presence of 'fever before rash' plus at least 7 or 8 of the 12 signs/symptoms demonstrated a more balanced performance between sensitivity and specificity.Laboratory-confirmed MPX and VZV cases presented with many of the same signs and symptoms, and the analysis here emphasized the utility of including 12 specific signs/symptoms when investigating MPX cases. In order to document and detect endemic human MPX cases, a surveillance case definition with more specificity is needed for accurate case detection. In the absence of a more specific case definition, continued emphasis on confirmatory laboratory-based diagnostics is warranted.

Definition study for variable cycle engine testbed engine and associated test program

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Vdoviak, J. W.

1978-01-01

The product/study double bypass variable cycle engine (VCE) was updated to incorporate recent improvements. The effect of these improvements on mission range and noise levels was determined. This engine design was then compared with current existing high-technology core engines in order to define a subscale testbed configuration that simulated many of the critical technology features of the product/study VCE. Detailed preliminary program plans were then developed for the design, fabrication, and static test of the selected testbed engine configuration. These plans included estimated costs and schedules for the detail design, fabrication and test of the testbed engine and the definition of a test program, test plan, schedule, instrumentation, and test stand requirements.

Diagnostic Reasoning and Cognitive Biases of Nurse Practitioners.

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Lawson, Thomas N

2018-04-01

Diagnostic reasoning is often used colloquially to describe the process by which nurse practitioners and physicians come to the correct diagnosis, but a rich definition and description of this process has been lacking in the nursing literature. A literature review was conducted with theoretical sampling seeking conceptual insight into diagnostic reasoning. Four common themes emerged: Cognitive Biases and Debiasing Strategies, the Dual Process Theory, Diagnostic Error, and Patient Harm. Relevant cognitive biases are discussed, followed by debiasing strategies and application of the dual process theory to reduce diagnostic error and harm. The accuracy of diagnostic reasoning of nurse practitioners may be improved by incorporating these items into nurse practitioner education and practice. [J Nurs Educ. 2018;57(4):203-208.]. Copyright 2018, SLACK Incorporated.

Systematic review and meta-analysis of studies evaluating diagnostic test accuracy: A practical review for clinical researchers-Part II. general guidance and tips

International Nuclear Information System (INIS)

Kim, Kyung Won; Choi, Sang Hyun; Huh, Jimi; Park, Seong Ho; Lee, June Young

2015-01-01

Meta-analysis of diagnostic test accuracy studies differs from the usual meta-analysis of therapeutic/interventional studies in that, it is required to simultaneously analyze a pair of two outcome measures such as sensitivity and specificity, instead of a single outcome. Since sensitivity and specificity are generally inversely correlated and could be affected by a threshold effect, more sophisticated statistical methods are required for the meta-analysis of diagnostic test accuracy. Hierarchical models including the bivariate model and the hierarchical summary receiver operating characteristic model are increasingly being accepted as standard methods for meta-analysis of diagnostic test accuracy studies. We provide a conceptual review of statistical methods currently used and recommended for meta-analysis of diagnostic test accuracy studies. This article could serve as a methodological reference for those who perform systematic review and meta-analysis of diagnostic test accuracy studies

Accuracy of an Immunochromatographic Diagnostic Test (ICT Malaria Combo Cassette Test) Compared to Microscopy among under Five-Year-Old Children when Diagnosing Malaria in Equatorial Guinea

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Portero, José-Luis; Rubio-Yuste, Maria; Descalzo, Miguel Angel; Raso, Jose; Lwanga, Magdalena; Obono, Jaquelina; Nseng, Gloria; Benito, Agustin; Cano, Jorge

2010-01-01

Conventional malaria diagnosis based on microscopy raises serious difficulties in weak health systems. Cost-effective and sensitive rapid diagnostic tests have been recently proposed as alternatives to microscopy. In Equatorial Guinea, a study was conducted to assess the reliability of a rapid diagnostic test compared to microscopy. The study was designed in accordance with the directives of the Standards for Reporting Diagnostic Accuracy Initiative (STARD). Peripheral thick and thin films for the microscopy diagnosis and a rapid immunochromatographic test (ICT Malaria Combo Cassette Test) were performed on under five-year-old children with malaria suspicion. The ICT test detected Plasmodium spp. infection with a sensitivity of 81.5% and a specificity of 81.9% while P. falciparum diagnosis occurred with a sensitivity of 69.7% and a specificity of 73.7%. The sensitivity of the ICT test increased with higher parasitemias. The general results showed little concordance between the ICT test and microscopy (kappa = 0.28, se: 0.04). In Equatorial Guinea, the ICT Malaria Combo Cassette Test has proven to be an acceptable test to detect high P. falciparum parasitemias. However, the decrease of sensitivity at medium and low parasitemias hampers that ICT can replace properly performed microscopy at present in the diagnosis of malaria in children. PMID:22332024

Evaluation of the diagnostic performance and operational characteristics of four rapid immunochromatographic syphilis tests in Burkina Faso.

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Bocoum, Fadima Yaya; Ouédraogo, Henri; Tarnagda, Grissoum; Kiba, Alice; Tiendrebeogo, Simon; Bationo, Fabrice; Liestman, Benjamin; Diagbouga, Serge; Zarowsky, Christina; Traoré, Ramata Ouédraogo; Kouanda, Séni

2015-06-01

Little information is available on the rapid diagnostic testing for syphilis in Burkina Faso. The objectives of the study were (i) to assess the sensitivity and specificity of four on site rapid tests in comparison with Treponema pallidum haemagglutination assay (TPHA) as a gold standard and (ii) to evaluate the operational characteristics of those tests among health workers in a maternity unit. Four rapid syphilis tests commercially available in Burkina Faso were evaluated using archived serum samples and Treponema pallidum hemagglutination assay (TPHA) as the gold standard. Blood samples were collected between November 2011 and June 2012 from blood donors at the Regional Blood Transfusion Center of Ouagadougou. The sensitivity and specificity of the tests were calculated. Evaluation of operational characteristics such as clarity of pamphlet, complexity of technique, duration, was conducted in a first-level healthcare center with health workers in maternity unit. Alere DetermineTM Syphilis was the most sensitive of the four rapid syphilis tests evaluated. It was followed by SD Bioline Syphilis 3.0, Cypress Diagnostics Syphilis Quick test and Accu-Tell ® Rapid Anti-TP, which was the least sensitive. The four tests demonstrated a good diagnostic specificity for syphilis (95-98%), and healthcare workers found them easy to use. The study allowed confirming the good performance of three of four rapid syphilis tests in Burkina Faso. More research will be conducted to assess the feasibility of introducing selected rapid tests for syphilis in antenatal care services.

Parallel Recovery in a Trilingual Speaker: The Use of the Bilingual Aphasia Test as a Diagnostic Complement to the Comprehensive Aphasia Test

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Green, David W.; Ruffle, Louise; Grogan, Alice; Ali, Nilufa; Ramsden, Sue; Schofield, Tom; Leff, Alex P.; Crinion, Jenny; Price, Cathy J.

2011-01-01

We illustrate the value of the Bilingual Aphasia Test in the diagnostic assessment of a trilingual speaker post-stroke living in England for whom English was a non-native language. The Comprehensive Aphasia Test is routinely used to assess patients in English, but only in combination with the Bilingual Aphasia Test is it possible and practical to…

Accuracy of Triple Diagnostic Test in Patients with Thyroid Nodule at Dr. Cipto Mangunkusumo General Hospital

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Diani Kartini

2017-04-01

Full Text Available The aim of the study is to evaluate the accuracy of triple diagnostic test on thyroid nodules. The data from patients’ medical records who came to Cipto Mangunkusumo General Hospital for the first time or for evaluation of thyroid nodule and patients who underwent thyroidectomy during 2010 to 2011. Clinical examination was scored by McGill Thyroid Nodule Score. ROC procedure was performed to obtain clinical cut-off scores of diagnosis of malignant. Ultrasonography (USG result was considered malignant for TIRADS 4, 5, and 6. If clinical, USG and histopathology examinations of triple diagnostic give positive results, it will be classified as concordant malignant whereas if all those three show benign results, the classification is benign. Thyroid carcinoma was found in 134 out of 161 patients with thyroid nodule. There were 84 patients with concordant results for all three elements of the triple test. Out of 84 patients with concordant triple diagnostic results, there were 53 malignant cases (32.9% and 31 benign cases (19.3%. Main histopathological findings among patients with thyroid carcinoma was papillary (90.3%, follicular (3%, medullary (0.7%, and anaplastic (6%. The sensitivity and specificity of triple diagnostic was 77% and 94%, with positive predictive value of 98%, negative predictive value of 51,6% and accuracy of 80.9%. Combination of clinical findings, USG, and FNAB gave malignant probability of 92%, better than combination of clinical findings and USG (81.6% or clinical findings and FNAB (87%. Triple diagnostic cannot be used as an ideal test to replace frozen section examination in managing thyroid nodule. However, in cases with concordant results of each triple diagnostic’s element, the positive predictive value (98% and malignant probability (92% is high. Keywords: thyroid nodule, triple diagnostic, accuracy.   Akurasi Metode Triple Diagnostic pada Pasien Nodul Tiroid  di RSUPN Dr. Cipto Mangunkusumo   Abstrak Tujuan

Self Diagnostic Accelerometer Ground Testing on a C-17 Aircraft Engine

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Tokars, Roger P.; Lekki, John D.

2013-01-01

The self diagnostic accelerometer (SDA) developed by the NASA Glenn Research Center was tested for the first time in an aircraft engine environment as part of the Vehicle Integrated Propulsion Research (VIPR) program. The VIPR program includes testing multiple critical flight sensor technologies. One such sensor, the accelerometer, measures vibrations to detect faults in the engine. In order to rely upon the accelerometer, the health of the accelerometer must be ensured. Sensor system malfunction is a significant contributor to propulsion in flight shutdowns (IFSD) which can lead to aircraft accidents when the issue is compounded with an inappropriate crew response. The development of the SDA is important for both reducing the IFSD rate, and hence reducing the rate at which this component failure type can put an aircraft in jeopardy, and also as a critical enabling technology for future automated malfunction diagnostic systems. The SDA is a sensor system designed to actively determine the accelerometer structural health and attachment condition, in addition to making vibration measurements. The SDA uses a signal conditioning unit that sends an electrical chirp to the accelerometer and recognizes changes in the response due to changes in the accelerometer health and attachment condition. In an effort toward demonstrating the SDAs flight worthiness and robustness, multiple SDAs were mounted and tested on a C-17 aircraft engine. The engine test conditions varied from engine off, to idle, to maximum power. The two SDA attachment conditions used were fully tight and loose. The newly developed SDA health algorithm described herein uses cross correlation pattern recognition to discriminate a healthy from a faulty SDA. The VIPR test results demonstrate for the first time the robustness of the SDA in an engine environment characterized by high vibration levels.

Development and assessment of molecular diagnostic tests for 15 enteropathogens causing childhood diarrhoea: a multicentre study.

Science.gov (United States)

Liu, Jie; Kabir, Furqan; Manneh, Jainaba; Lertsethtakarn, Paphavee; Begum, Sharmin; Gratz, Jean; Becker, Steve M; Operario, Darwin J; Taniuchi, Mami; Janaki, Lalitha; Platts-Mills, James A; Haverstick, Doris M; Kabir, Mamun; Sobuz, Shihab U; Nakjarung, Kaewkanya; Sakpaisal, Pimmada; Silapong, Sasikorn; Bodhidatta, Ladaporn; Qureshi, Shahida; Kalam, Adil; Saidi, Queen; Swai, Ndealilia; Mujaga, Buliga; Maro, Athanasia; Kwambana, Brenda; Dione, Michel; Antonio, Martin; Kibiki, Gibson; Mason, Carl J; Haque, Rashidul; Iqbal, Najeeha; Zaidi, Anita K M; Houpt, Eric R

2014-08-01

Childhood diarrhoea can be caused by many pathogens that are difficult to assay in the laboratory. Molecular diagnostic techniques provide a uniform method to detect and quantify candidate enteropathogens. We aimed to develop and assess molecular tests for identification of enteropathogens and their association with disease. We developed and assessed molecular diagnostic tests for 15 enteropathogens across three platforms-PCR-Luminex, multiplex real-time PCR, and TaqMan array card-at five laboratories worldwide. We judged the analytical and clinical performance of these molecular techniques against comparator methods (bacterial culture, ELISA, and PCR) using 867 diarrhoeal and 619 non-diarrhoeal stool specimens. We also measured molecular quantities of pathogens to predict the association with diarrhoea, by univariate logistic regression analysis. The molecular tests showed very good analytical and clinical performance at all five laboratories. Comparator methods had limited sensitivity compared with the molecular techniques (20-85% depending on the target) but good specificity (median 97·3%, IQR 96·5-98·9; mean 95·2%, SD 9·1). Positive samples by comparator methods usually had higher molecular quantities of pathogens than did negative samples, across almost all platforms and for most pathogens (pMolecular diagnostic tests can be implemented successfully and with fidelity across laboratories around the world. In the case of diarrhoea, these techniques can detect pathogens with high sensitivity and ascribe diarrhoeal associations based on quantification, including in mixed infections, providing rich and unprecedented measurements of infectious causes. Bill & Melinda Gates Foundation Next Generation Molecular Diagnostics Project. Copyright © 2014 Elsevier Ltd. All rights reserved.

Systematic review, meta-analysis and economic modelling of molecular diagnostic tests for antibiotic resistance in tuberculosis.

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Drobniewski, Francis; Cooke, Mary; Jordan, Jake; Casali, Nicola; Mugwagwa, Tendai; Broda, Agnieszka; Townsend, Catherine; Sivaramakrishnan, Anand; Green, Nathan; Jit, Mark; Lipman, Marc; Lord, Joanne; White, Peter J; Abubakar, Ibrahim

2015-05-01

Drug-resistant tuberculosis (TB), especially multidrug-resistant (MDR, resistance to rifampicin and isoniazid) disease, is associated with a worse patient outcome. Drug resistance diagnosed using microbiological culture takes days to weeks, as TB bacteria grow slowly. Rapid molecular tests for drug resistance detection (1 day) are commercially available and may promote faster initiation of appropriate treatment. To (1) conduct a systematic review of evidence regarding diagnostic accuracy of molecular genetic tests for drug resistance, (2) conduct a health-economic evaluation of screening and diagnostic strategies, including comparison of alternative models of service provision and assessment of the value of targeting rapid testing at high-risk subgroups, and (3) construct a transmission-dynamic mathematical model that translates the estimates of diagnostic accuracy into estimates of clinical impact. A standardised search strategy identified relevant studies from EMBASE, PubMed, MEDLINE, Bioscience Information Service (BIOSIS), System for Information on Grey Literature in Europe Social Policy & Practice (SIGLE) and Web of Science, published between 1 January 2000 and 15 August 2013. Additional 'grey' sources were included. Quality was assessed using quality assessment of diagnostic accuracy studies version 2 (QUADAS-2). For each diagnostic strategy and population subgroup, a care pathway was constructed to specify which medical treatments and health services that individuals would receive from presentation to the point where they either did or did not complete TB treatment successfully. A total cost was estimated from a health service perspective for each care pathway, and the health impact was estimated in terms of the mean discounted quality-adjusted life-years (QALYs) lost as a result of disease and treatment. Costs and QALYs were both discounted at 3.5% per year. An integrated transmission-dynamic and economic model was used to evaluate the cost-effectiveness of

Systematic review, meta-analysis and economic modelling of molecular diagnostic tests for antibiotic resistance in tuberculosis.

Science.gov (United States)

Drobniewski, Francis; Cooke, Mary; Jordan, Jake; Casali, Nicola; Mugwagwa, Tendai; Broda, Agnieszka; Townsend, Catherine; Sivaramakrishnan, Anand; Green, Nathan; Jit, Mark; Lipman, Marc; Lord, Joanne; White, Peter J; Abubakar, Ibrahim

2015-01-01

BACKGROUND Drug-resistant tuberculosis (TB), especially multidrug-resistant (MDR, resistance to rifampicin and isoniazid) disease, is associated with a worse patient outcome. Drug resistance diagnosed using microbiological culture takes days to weeks, as TB bacteria grow slowly. Rapid molecular tests for drug resistance detection (1 day) are commercially available and may promote faster initiation of appropriate treatment. OBJECTIVES To (1) conduct a systematic review of evidence regarding diagnostic accuracy of molecular genetic tests for drug resistance, (2) conduct a health-economic evaluation of screening and diagnostic strategies, including comparison of alternative models of service provision and assessment of the value of targeting rapid testing at high-risk subgroups, and (3) construct a transmission-dynamic mathematical model that translates the estimates of diagnostic accuracy into estimates of clinical impact. REVIEW METHODS AND DATA SOURCES A standardised search strategy identified relevant studies from EMBASE, PubMed, MEDLINE, Bioscience Information Service (BIOSIS), System for Information on Grey Literature in Europe Social Policy & Practice (SIGLE) and Web of Science, published between 1 January 2000 and 15 August 2013. Additional 'grey' sources were included. Quality was assessed using quality assessment of diagnostic accuracy studies version 2 (QUADAS-2). For each diagnostic strategy and population subgroup, a care pathway was constructed to specify which medical treatments and health services that individuals would receive from presentation to the point where they either did or did not complete TB treatment successfully. A total cost was estimated from a health service perspective for each care pathway, and the health impact was estimated in terms of the mean discounted quality-adjusted life-years (QALYs) lost as a result of disease and treatment. Costs and QALYs were both discounted at 3.5% per year. An integrated transmission-dynamic and

Decision making about healthcare-related tests and diagnostic test strategies. Paper 2: a review of methodological and practical challenges

NARCIS (Netherlands)

Mustafa, Reem A.; Wiercioch, Wojtek; Cheung, Adrienne; Prediger, Barbara; Brozek, Jan; Bossuyt, Patrick; Garg, Amit X.; Lelgemann, Monika; Büehler, Diedrich; Schünemann, Holger J.

2017-01-01

Objectives: In this first of a series of five articles, we provide an overview of how and why healthcare-related tests and diagnostic strategies are currently applied. We also describe how our findings can be integrated with existing frameworks for making decisions that guide the use of

EULAR points to consider in the development of classification and diagnostic criteria in systemic vasculitis

DEFF Research Database (Denmark)

Basu, Neil; Watts, Richard; Bajema, Ingeborg

2010-01-01

The systemic vasculitides are multiorgan diseases where early diagnosis and treatment can significantly improve outcomes. Robust nomenclature reduces diagnostic delay. However, key aspects of current nomenclature are widely perceived to be out of date, these include disease definitions, classific......, classification and diagnostic criteria. Therefore, the aim of the present work was to identify deficiencies and provide contemporary points to consider for the development of future definitions and criteria in systemic vasculitis....

Diagnostic value of Pentraxin-3 in patients with sepsis and septic shock in accordance with latest sepsis-3 definitions.

Science.gov (United States)

Hamed, Sonja; Behnes, Michael; Pauly, Dominic; Lepiorz, Dominic; Barre, Max; Becher, Tobias; Lang, Siegfried; Akin, Ibrahim; Borggrefe, Martin; Bertsch, Thomas; Hoffmann, Ursula

2017-08-09

Pentraxin-3 (PTX-3) is an acute-phase protein involved in inflammatory and infectious processes. This study assesses its diagnostic and prognostic value in patients with sepsis or septic shock in a medical intensive care unit (ICU). The study includes 213 ICU patients with clinical criteria of sepsis and septic shock. 77 donors served as controls. Plasma levels of PTX-3, procalcitonin (PCT) and interleukin-6 were measured on day 1, 3 and 8. PTX-3 correlated with higher lactate levels as well as with APACHE II and SOFA scores (p = 0.0001). PTX-3 levels of patients with sepsis or septic shock were consistently significantly higher than in the control group (p ≤ 0.001). Plasma levels were able to discriminate sepsis and septic shock significantly on day 1, 3 and 8 (range of AUC 0.73-0.92, p = 0.0001). Uniform cut-off levels were defined at ≥5 ng/ml for at least sepsis, ≥9 ng/ml for septic shock (p = 0.0001). PTX-3 reveals diagnostic value for sepsis and septic shock during the first week of intensive care treatment, comparable to interleukin-6 according to latest Sepsis-3 definitions. NCT01535534 . Registered 14.02.2012.

Diagnostic tests and algorithms used in the investigation of haematuria: systematic reviews and economic evaluation.

Science.gov (United States)

Rodgers, M; Nixon, J; Hempel, S; Aho, T; Kelly, J; Neal, D; Duffy, S; Ritchie, G; Kleijnen, J; Westwood, M

2006-06-01

To determine the most effective diagnostic strategy for the investigation of microscopic and macroscopic haematuria in adults. Electronic databases from inception to October 2003, updated in August 2004. A systematic review was undertaken according to published guidelines. Decision analytic modelling was undertaken, based on the findings of the review, expert opinion and additional information from the literature, to assess the relative cost-effectiveness of plausible alternative tests that are part of diagnostic algorithms for haematuria. A total of 118 studies met the inclusion criteria. No studies that evaluated the effectiveness of diagnostic algorithms for haematuria or the effectiveness of screening for haematuria or investigating its underlying cause were identified. Eighteen out of 19 identified studies evaluated dipstick tests and data from these suggested that these are moderately useful in establishing the presence of, but cannot be used to rule out, haematuria. Six studies using haematuria as a test for the presence of a disease indicated that the detection of microhaematuria cannot alone be considered a useful test either to rule in or rule out the presence of a significant underlying pathology (urinary calculi or bladder cancer). Forty-eight of 80 studies addressed methods to localise the source of bleeding (renal or lower urinary tract). The methods and thresholds described in these studies varied greatly, precluding any estimate of a 'best performance' threshold that could be applied across patient groups. However, studies of red blood cell morphology that used a cut-off value of 80% dysmorphic cells for glomerular disease reported consistently high specificities (potentially useful in ruling in a renal cause for haematuria). The reported sensitivities were generally low. Twenty-eight studies included data on the accuracy of laboratory tests (tumour markers, cytology) for the diagnosis of bladder cancer. The majority of tumour marker studies

Veterinary Molecular Diagnostics

NARCIS (Netherlands)

Roest, H.I.J.; Engelsma, M.Y.; Weesendorp, E.; Bossers, A.; Elbers, A.R.W.

2017-01-01

In veterinary molecular diagnostics, samples originating from animals are tested. Developments in the farm animals sector and in our societal attitude towards pet animals have resulted in an increased demand for fast and reliable diagnostic techniques. Molecular diagnostics perfectly matches this

Introduction of spirometry into clinical practice in Georgetown, Guyana: quality and diagnostic outcomes.

Science.gov (United States)

Johnston, J C; Rempel, C; Sanders, C; Piggott, E; Maxwell, Y; Jaipersaud, K; Luknauth, R; Persaud, D; Rambaran, M; Levy, R D

2016-09-01

Georgetown Public Hospital Corporation (GPHC), a 600-bed publicly funded referral hospital in Georgetown, Guyana. To assess spirometry quality and diagnostic outcomes 2 years after the introduction of spirometry into routine clinical practice at GPHC. We performed a retrospective review of 476 consecutive spirometry assessments performed from November 2013 to November 2015. We assessed the proportion and trend of spirometry tests meeting acceptability criteria, along with diagnostic interpretations and spirometry laboratory referral patterns. Overall, 80.4% of the 454 initial spirometry measurements on unique patients met the acceptability criteria, with no significant change in the proportion of acceptable spirometry over the study period (P = 0.450). Of the 369 (81.3%) first tests considered interpretable, 139 (30.6%) were normal, 151 (33.3%) were obstructive, 54 (11.9%) were suggestive of a restrictive pattern, 25 (5.5%) were suggestive of a mixed disorder and 119 (26.2%) tests met the definition of reversibility. Over a 2-year period, high-quality spirometry was performed in GPHC, a publicly funded hospital in a middle-income country with no pre-existing specialised respiratory service.

Recent Progress in the Development of Diagnostic Tests for Malaria.

Science.gov (United States)

Krampa, Francis D; Aniweh, Yaw; Awandare, Gordon A; Kanyong, Prosper

2017-09-19

The impact of malaria on global health has continually prompted the need to develop effective diagnostic strategies. In malaria endemic regions, routine diagnosis is hampered by technical and infrastructural challenges to laboratories. These laboratories lack standard facilities, expertise or diagnostic supplies; thus, therapy is administered based on clinical or self-diagnosis. There is the need for accurate diagnosis of malaria due to the continuous increase in the cost of medication, and the emergence and spread of drug resistant strains. However, the widely utilized Giemsa-stained microscopy and immunochromatographic tests for malaria are liable to several drawbacks, including inadequate sensitivity and false-positive outcomes. Alternative methods that offer improvements in performance are either expensive, have longer turnaround time or require a level of expertise that makes them unsuitable for point-of-care (POC) applications. These gaps necessitate exploration of more efficient detection techniques with the potential of POC applications, especially in resource-limited settings. This minireview discusses some of the recent trends and new approaches that are seeking to improve the clinical diagnosis of malaria.

Recent Progress in the Development of Diagnostic Tests for Malaria

Directory of Open Access Journals (Sweden)

Francis D. Krampa

2017-09-01

Full Text Available The impact of malaria on global health has continually prompted the need to develop effective diagnostic strategies. In malaria endemic regions, routine diagnosis is hampered by technical and infrastructural challenges to laboratories. These laboratories lack standard facilities, expertise or diagnostic supplies; thus, therapy is administered based on clinical or self-diagnosis. There is the need for accurate diagnosis of malaria due to the continuous increase in the cost of medication, and the emergence and spread of drug resistant strains. However, the widely utilized Giemsa-stained microscopy and immunochromatographic tests for malaria are liable to several drawbacks, including inadequate sensitivity and false-positive outcomes. Alternative methods that offer improvements in performance are either expensive, have longer turnaround time or require a level of expertise that makes them unsuitable for point-of-care (POC applications. These gaps necessitate exploration of more efficient detection techniques with the potential of POC applications, especially in resource-limited settings. This minireview discusses some of the recent trends and new approaches that are seeking to improve the clinical diagnosis of malaria.

Delivering Diagnostic Quality Video over Mobile Wireless Networks for Telemedicine

Directory of Open Access Journals (Sweden)

Sira P. Rao

2009-01-01

Full Text Available In real-time remote diagnosis of emergency medical events, mobility can be enabled by wireless video communications. However, clinical use of this potential advance will depend on definitive and compelling demonstrations of the reliability of diagnostic quality video. Because the medical domain has its own fidelity criteria, it is important to incorporate diagnostic video quality criteria into any video compression system design. To this end, we used flexible algorithms for region-of-interest (ROI video compression and obtained feedback from medical experts to develop criteria for diagnostically lossless (DL quality. The design of the system occurred in three steps-measurement of bit rate at which DL quality is achieved through evaluation of videos by medical experts, incorporation of that information into a flexible video encoder through the notion of encoder states, and an encoder state update option based on a built-in quality criterion. Medical experts then evaluated our system for the diagnostic quality of the video, allowing us to verify that it is possible to realize DL quality in the ROI at practical communication data transfer rates, enabling mobile medical assessment over bit-rate limited wireless channels. This work lays the scientific foundation for additional validation through prototyped technology, field testing, and clinical trials.

Surface enhanced Raman spectroscopy (SERS for in vitro diagnostic testing at the point of care

Directory of Open Access Journals (Sweden)

Marks Haley

2017-06-01

Full Text Available Point-of-care (POC device development is a growing field that aims to develop low-cost, rapid, sensitive in-vitro diagnostic testing platforms that are portable, self-contained, and can be used anywhere – from modern clinics to remote and low resource areas. In this review, surface enhanced Raman spectroscopy (SERS is discussed as a solution to facilitating the translation of bioanalytical sensing to the POC. The potential for SERS to meet the widely accepted “ASSURED” (Affordable, Sensitive, Specific, User-friendly, Rapid, Equipment-free, and Deliverable criterion provided by the World Health Organization is discussed based on recent advances in SERS in vitro assay development. As SERS provides attractive characteristics for multiplexed sensing at low concentration limits with a high degree of specificity, it holds great promise for enhancing current efforts in rapid diagnostic testing. In outlining the progression of SERS techniques over the past years combined with recent developments in smart nanomaterials, high-throughput microfluidics, and low-cost paper diagnostics, an extensive number of new possibilities show potential for translating SERS biosensors to the POC.

Surface enhanced Raman spectroscopy (SERS) for in vitro diagnostic testing at the point of care

Science.gov (United States)

Marks, Haley; Schechinger, Monika; Garza, Javier; Locke, Andrea; Coté, Gerard

2017-06-01

Point-of-care (POC) device development is a growing field that aims to develop low-cost, rapid, sensitive in-vitro diagnostic testing platforms that are portable, self-contained, and can be used anywhere - from modern clinics to remote and low resource areas. In this review, surface enhanced Raman spectroscopy (SERS) is discussed as a solution to facilitating the translation of bioanalytical sensing to the POC. The potential for SERS to meet the widely accepted "ASSURED" (Affordable, Sensitive, Specific, User-friendly, Rapid, Equipment-free, and Deliverable) criterion provided by the World Health Organization is discussed based on recent advances in SERS in vitro assay development. As SERS provides attractive characteristics for multiplexed sensing at low concentration limits with a high degree of specificity, it holds great promise for enhancing current efforts in rapid diagnostic testing. In outlining the progression of SERS techniques over the past years combined with recent developments in smart nanomaterials, high-throughput microfluidics, and low-cost paper diagnostics, an extensive number of new possibilities show potential for translating SERS biosensors to the POC.

Plain abdominal radiographs in patients with Crohn's disease: radiological findings and diagnostic value.

LENUS (Irish Health Repository)

O'Regan, K

2012-08-01

To determine the diagnostic yield and clinical value of plain film of the abdomen (PFA) in Crohn\\'s disease (CD) patients and to determine whether performance of PFA yields definitive diagnostic information or whether additional imaging examinations are required.

Progeria Research Foundation Diagnostic Testing Program

Science.gov (United States)

... Share the DVD Meet the Kids in the Movie Bring LATS to the classroom! Close News/Events ... this could severely affect their research results and interpretation. Through the PRF Diagnostics Program, each cell line ...

A preface on advances in diagnostics for infectious and parasitic diseases: detecting parasites of medical and veterinary importance.

Science.gov (United States)

Stothard, J Russell; Adams, Emily

2014-12-01

There are many reasons why detection of parasites of medical and veterinary importance is vital and where novel diagnostic and surveillance tools are required. From a medical perspective alone, these originate from a desire for better clinical management and rational use of medications. Diagnosis can be at the individual-level, at close to patient settings in testing a clinical suspicion or at the community-level, perhaps in front of a computer screen, in classification of endemic areas and devising appropriate control interventions. Thus diagnostics for parasitic diseases has a broad remit as parasites are not only tied with their definitive hosts but also in some cases with their vectors/intermediate hosts. Application of current diagnostic tools and decision algorithms in sustaining control programmes, or in elimination settings, can be problematic and even ill-fitting. For example in resource-limited settings, are current diagnostic tools sufficiently robust for operational use at scale or are they confounded by on-the-ground realities; are the diagnostic algorithms underlying public health interventions always understood and well-received within communities which are targeted for control? Within this Special Issue (SI) covering a variety of diseases and diagnostic settings some answers are forthcoming. An important theme, however, throughout the SI is to acknowledge that cross-talk and continuous feedback between development and application of diagnostic tests is crucial if they are to be used effectively and appropriately.

International survey among orthopaedic trauma surgeons: Lack of a definition of fracture-related infection.

Science.gov (United States)

Morgenstern, M; Moriarty, T F; Kuehl, R; Richards, R G; McNally, M A; Verhofstad, M H J; Borens, O; Zalavras, C; Raschke, M; Kates, S L; Metsemakers, W J

2018-03-01

Fracture-related infection (FRI) is one of the most challenging musculoskeletal complications in orthopaedic-trauma surgery. Although the orthopaedic community has developed and adopted a consensus definition of prosthetic joint infections (PJI), it still remains unclear how the trauma surgery community defines FRI in daily clinical practice or in performing clinical research studies. The central aim of this study was to survey the opinions of a global network of trauma surgeons on the definitions and criteria they routinely use, and their opinion on the need for a unified definition of FRI. The secondary aims were to survey their opinion on the utility of currently used definitions that may be at least partially applicable for FRI, and finally their opinion on the important clinical parameters that should be considered as diagnostic criteria for FRI. An 11-item questionnaire was developed to cover the above-mentioned aims. The questionnaire was administered by SurveyMonkey and was sent via blast email to all registered users of AO Trauma (Davos, Switzerland). Out of the 26'563 recipients who opened the email, 2'327 (8.8%) completed the questionnaire. Nearly 90% of respondents agreed that a consensus-derived definition for FRI is required and 66% of the surgeons also agreed that PJI and FRI are not equal with respect to diagnosis, treatment and outcome. Furthermore, "positive cultures from microbiology testing", "elevation of CRP", "purulent drainage" and "local clinical signs of infection" were voted the most important diagnostic parameters for FRI. This international survey infers the need for a consensus definition of FRI and provides insight into the clinical parameters seen by an international community of trauma surgeons as being critical for defining FRI. Copyright © 2018 Elsevier Ltd. All rights reserved.